Jin

For 1980 through 1990, the average weekly earnings (in dollars)for workers in the United States can be modeled by E= 14.5t + 270, where t is the number of years since 1980. Approximate the average weekly earnings in 1980 and 1990. I am having trouble unde...

20 years ago

I know how environmental science branches off to various sciences- how does astronomy (to be specific, the discovery that Pluto's not a planet anymore) relates to environmental science? Thank you! Reclassifying Pluto as "not a planet" is NOT a discovery....

19 years ago

Are there any connections between evolution and environmental science-- if there is, what is it? Thanks! Weren't many lakes back in time very acid? I wonder if acid rain is favoring certain mutations in organisms? Will that affect evolution? I didn't quit...

19 years ago

I'm having trouble understanding what kind of sentences these are: Compound? Compound-complex? Declarative? Interrogative? Imperative? Loose? Periodic? Thank you! Tyr here: http://www.eslincanada.com/englishlesson2.html Then here: http://www.arts.uottawa....

19 years ago

what is the derivative of sin(x^(1/2)) and (sin(x))^(1/2)? Is there a difference? Thanks! Yes, there is a difference. Use the chain rule.

19 years ago

How would you define balanced sentences? Could you give me some examples? Thanks! Balance in writing sentences is generally called "parallelism". OWL the online writing lab has this definition. "Parallel structure means using the same pattern of words to...

19 years ago

I am finding the second derivative of (x^2)(y^3) = 1 2x(y^3) + (x^2)(y')(3y^2) = 0 And I simplified the answer to y'= (-2y)/(3x) so it would be... [(-2y')(3x)-(-2y)(3)]/(9x^2) and it's simplified to (-6xy'+6y)/(9x^2)= y'' I could plug in (-2y)/(3x) in pla...

19 years ago

Need help in unscrambling this phrase: MTLEFKOTRYETEEMCISRTRAE for what subject?Is this for What subject is this for? capilpsean (toy) ttstelli can you unsramble this (ttstelli) resdoita Littlest

19 years ago

Find the volume of the solid whose base is the region bounded by the graphs of y=x^3,x=1, and the x-axis, and whose cross sections perpenditular to the x-axis are semicircles. What would be the radius in this case? I thought it would just be x^3, but othe...

18 years ago

If you have a geometric alternating series, and you prove that the series is converging by doing geometric series test, and NOT alternating series test, then does that allow you to say that the series converges ABSOLUTELY? Or should you do alternate serie...

18 years ago

I know how to find the interval of convergence, but I don't understand when to check for convergence at the endpoints (to see if I should include it or not) Could someone help me understand this? Thanks!

18 years ago

Topic being the linearization (finding the equation of the tangent lines), how do you determine if it's overestimate or underestimate? thanks!

18 years ago

why does pH of the matrix increase when electrons flow along the electron transport chains of mitochondria?

17 years ago

I had to observe slides of onion root tip to study plant mitosis. And the question I have to answer asks,if your observations had not been restricted to the area of the root tip that is actively dividing, how would your results have been different? I beli...

17 years ago

What effect does water loss (through heavy perpiration) have on a person's endocrine system?

17 years ago

Would you expect the dissolved oxygen concentration of water samples taken from a lake at 7 am to be higher or lower than samples takn at 5 pm? I feel like there may be more dissolved oxygen in the sample taken at 7 am because photosynthesis probably took...

17 years ago

How does the frequency of interest compounding, regardless of the rate of interest or period of accumulation, affect the future value of any given amount?

16 years ago

How does discounted cash flow differ from the other valuation methods?

16 years ago

In Figure (a), a block of mass m lies on a horizontal frictionless surface and is attached to one end of a horizontal spring (spring constant k) whose other end is fixed. The block is initially at rest at the position where the spring is unstretched (x =...

15 years ago

A skier leaves the end of a ramp with a velocity of 25.3 m/s and lands 50.3 m from the base of the ramp. How high is the end of the ramp from the ground?

15 years ago

Wile E. Coyote is holding a “HEAVY DUTY ACME ANVIL” on a cliff that is 40.0 meters high. The Roadrunner (beep-beep), who is 1.0 meter tall, is running on a road toward the cliff at a constant velocity of 10.0 m/s. Wile E. Coyote wants to drop the anvil on...

15 years ago

The Fe(ox)33– complex ion creates an emerald green solution when dissolved. The observed solution color of the complex indicates the size of o is: A. large. B. small. C. in between. D. inconclusive, more information is needed. The observed solution color...

15 years ago

for SCN- if S-C has a bond order of 1, S=C and C=N have bond orders of 2, and C triple bond N hasa bond order of 3, ... Do the bond length in SCN- point to one resonance structure over the other? Which one?

15 years ago

The pKa for hydrochloric acid is −6.0. What is the concentration of HCl(aq) we would expect to find in a 1 M solution of hydrochloric acid? What pH would we expect? how do you solve this problem?

15 years ago

Which reactants in the reactions below are acting as Br©ªnsted-Lowry bases? NH4 +(aq) + OH−(aq) <-> NH3(aq) + H2O(l) H2PO4 −(aq) + H2O(l) <-> H3O+(aq) + HPO4 2−(aq) is the answer H2O and the H3O+

15 years ago

how do you solve this? What is the pH of the solution created by combining 12.30 mL of the 0.10 M NaOH(aq) with 8.00 mL of the 0.10 M HCl(aq)? with 8.00 mL of the 0.10 M HC2H3O2(aq)? mL NaOH pH wHCl pH wHC2H3O2 12.30 Complete the table below: What are the...

15 years ago

Determine the overall orders of the reactions to which the following rate laws apply: a) rate= k[NO2]^2 b) rate = k c) k [H2][Br2]^1/2 d) k [NO]^2[O2] is it.. a. 2 b. 0 c. 1 1/2 d. 3

15 years ago

how do you solve this problem? consider the reaction A->B the rate of the reaction is 1.6 x 10^-2 M/s when the concentration of A is 0.35 M. Calculate the rate constant if the reaction is a) first order in A and b) second order in A.

15 years ago

the chapter is about chemical kinetics Reaction mechanisms: What does it mean by mechanism of a reaction? What is an elementary step? what is the molecularity of a reaction?

15 years ago

How do you solve this problem? In a certain industrial process involving a heterogeneous catalyst, the volume of the catalyst (in the shape of a shpere) is 10.0cm^3. Calculate the surface area of the catalyst. IF the sphere is broken down into eight spher...

15 years ago

The amount of indicator used in an acid-base titration must be small. why??

15 years ago

Write balanced equations and solubility product expressions for the solubility equlibria of the following compounds: a. CuBr b. ZnC2O4 c. Ag2CrO4 d. Hg2Cl2 e. AuCl3 f. Mn3(po4)2 can you give me some examples using the compounds given?

15 years ago

Solid NaI is slowly added to a soln that is 0.010M in Cu+ and 0.010M in Ag+. a. Which compound will begin to precipitate first? b. Calculate [Ag+] when CuI just begins to precipitate/ c. What percent of Ag+ remains in solution at this point?

15 years ago

Explain, with balanced ionic equations, why a. CuI2 dissolves in ammonia solution b. AgBr dissolves in NaCN solution, c. HgCl2 dissolves in KCL solution.

15 years ago

Discuss the spontaneity of an electrochemical reaction in terms of its standard emf (E¨¬cell)

15 years ago

I had this on a test, not sure how to do it Explain, using balanced chemical reactions with the smallest integer coefficients, why each of following occurs. a. CuI2 (insoluble in pure water) dissolves readily in aqueous ammonia, HN3(aq) b. AgBr (insoluble...

15 years ago

7.50gram quantity of a diprotic acid was dissolved in water and made up to exactly 250ml. If 25ml of this solution were neutralized by 11.1 mL of 1.0 M KOH then what is the molar mass of the acid? I did 7.50/5.55x10^-3

15 years ago

The values of Ksp for AgBr and AgCl, are 7.7x10^-13 and 1.6 x 10^-10. A solution containing a mixture of 2.0x10^-2 M Br and 2.0 x 10^-2M Cl is a candidate for separating using selective precipitation. Solid AgNO3 is added, with a miniature spatula, and wi...

15 years ago

How do you know if these solutions are acidic, basic, or nearly neutral? a. NH4NO2 b. Cr(NO3)3

15 years ago

Determine the oxidation state of each transition metal in the following cmpds. (a) Na2MoO4 (b) KAuCl4 (c) MgWO4 and (d) Ni(CO)4

15 years ago

To have a color, the transition metal complex should have an electron in a d-orbital, and an unoccupied spot in a higher energy d-orbital. • Practice Problem. • Predict whether each of the following complexes could be colored: (a) [Sc(H2O)6]3+ (b) [Ti(H2O...

15 years ago

Faraday¡¯s Law of Electrolysis • Practice Problem. • What is the oxidation state of the osmium atom in an unknown salt if 26.7 grams of osmium plate out when a current of 15 amps is passed through a solution of this salt for 1 hour?

15 years ago

why is it that [H2O] is NOT included in the rate law, even though it is a reactant?

15 years ago

why is it that [H2O] is NOT included in the rate law, even though it is a reactant?

15 years ago

Which of the following when added to 100.0mL of a 0.100M soln of NH4Cl would produce a buffer soln? a.100.0mL of 0.100 M HCl soln b. 100.0mL of 0.050M NaOH soln c. 100.0mL of 0.100M NaOH soln d. 100.0mL of 0.050M NH4No3 soln e.none of the above

15 years ago

In titration of a 0.10M soln of Na2Co3 with HCL which of the following will be present in the largest concentration at the first equivalence point? a. Co3^2- b. HCO3- c. H+ d. H2CO3 e. OH-

15 years ago

A salt that could decrease the ionization of HCOl in soln is probably a. NaOH b. NaCl c. NaOCl d. NaH e. none of these how would you solve this

15 years ago

Which of the following salts would show an appreciable pH-dependent solubility? a. AgCl b. Mg(OH)2 c. BaF d. both b and c e. all of the above I put c as my answer (not sure if its right, but can you explain how you would solve this)

15 years ago

how do you solve this? The candy indistry converts sucrose (C11H22O11,table sugar),a crystalline material, to invert sugar, a hydrolzyed [rpdict tjat os 50:50 frutose and glucose. The hydrolysis occurs in water, quite slowly, at an elevated temperature of...

15 years ago

Rates of chemical reactions usually depend on temperature and pressure. However, half-life of all radioactive elements is independent of both T and p. How can these decay rates be independent of T if we beleive in the Arrhenius equation?

15 years ago

find the domain of function f(x)= (5x + 4)/(x^2 + 3x + 2) is the answer.. x can't be -2 or -1?

15 years ago

if f(x)is greater or equal to 10x–42 but less than or equal to x2+2x–26 determine limx4f(x) = What theorem did you use to arrive at your answer?

15 years ago

If a ball is thrown straight up into the air with an initial velocity of 95 ft/s, it height in feet after t second is given by y=95t–16t2. Find the average velocity for the time period begining when t=1 and lasting (i) 01 seconds: (ii) 001 seconds: (iii)...

15 years ago

evaluate the limit as lim goes to -1 (x^2 +2x +1)/ (x^4 -1) the answer is zero but i don't know how to get it

15 years ago

evaluate the limit as lim h goes to 0 ((2+h)^3 - 8)/h the answer is twelve but I don't know how to factor out the cube

15 years ago

how do you factor our a cube? x^3 +8

15 years ago

In the theory of relativity, the mass of a particle with velocity v is m=mo/(square root ((1- v^ 2)/ c^2)) where mo is the mass of the particle at rest and ci s the speed of light. What happens as v goes to c?

15 years ago

I don't know how y-1=-1/3(x-3) is simplifes to x+3y-6=0

15 years ago

how do you find the derivative of square root of x

15 years ago

how does secx(tanx + tan^2x- sec^2x) simplified to sec x (tanx -1)?

15 years ago

how do you find sin7x/4x when lim x goes to 0 the answer is 7/4

15 years ago

how do you find the derivative of square root of 5 /t^5

15 years ago

If f(x)=(x^2+3x+4)^2 how do you find the derivative I tried doing 2 (2x+3)..

15 years ago

what is the derivative of f(x)=6sin2x I put 12cosx...

15 years ago

How do you find the derivative of square root of five /t^5? how do you find the derivative of square root of five /t^5 I know that f=a t^-n f'= -an t^(-n-1) and i tried putting -25/{[2sqrt(5/t^5)]/(t^4)}

15 years ago

Consider the function f(x)=–3x3–1x2+1x+1Find the average slope of this function on the interval (–2–1). By the Mean Value Theorem, we know there exists a c in the open interval (–2–1) such that f(c) is equal to this mean slope. Find the value of c in the...

15 years ago

f(x)=8x^3+1x^2–8x+2/–7x^2–4x+9 Find the equation of the non-vertical asymptote. y = Does f(x) intersect its non-vertical asymptote? (yes or no) What is the smallest value of x at which f(x) intersects its non-vertical asymptote? ( Enter No in the question...

15 years ago

find the derivative y= csc^-1 (secx) 0 less than or equal to x less than or equal to 2¤Ð what did i do wrong? - 1/ secx sqrt(secx^2 -1) * secxtanx

14 years ago

find all values of x for which function is differentiable. y=lnx^2 why is the answer= for all x doesn't equal 0?

14 years ago

A ball is thrown into the air with an upward velocity of 28 ft/s. Its height (h) in feet after t seconds is given by the function h = –16t² + 28t + 7. How long does it take the ball to reach its maximum height? What is the ball’s maximum height? How do I...

13 years ago

The decomposition reaction, x-->products, is second-order with rate constant k=0.0183 L/(s)(mol). How long will it take for the decomposition to be 95% complete, if the intitial concentration of X is 1.25mol/L? Thanks

11 years ago

According to the mechanism below, what is the correct expression for the rate consumption of A? In the mechanism, M is a molecule that collides with A and A* is a highly-energized for of A. Step 1: A+M <--> A*+M : rate constants k1 and k-1 Step 2: A* <-->...

11 years ago

A reaction has a first order rate constant of (6.25x10^-5 1/s) at T=298.15K and (0.0000538 1/s) at T=338.15K. What is the value of the rate constant at T=316.15K?

11 years ago

The activation energy, Ea, for a zeroth-order reaction, X-->products, is most readily obtained from the slope of a plot of: (choose from below) -[X] vs time -ln k vs time -rate vs time -[X]^2 vs time -ln[X] vs time -1/[X] vs time -ln k vs 1/T, where T is...

11 years ago

I'm working on substitution organic chemistry problems and I just had a question. There's an equation in which a molecule is treated with methanol in an acetone solution. Would the reaction be SN1 or SN2? I thought that it was SN2 because of the aprotic a...

10 years ago

An orange rolls across a table with a speed of 0.5 m/s and falls off the edge. If it lands 3 m from the edge of the table, from what height does it fall?

10 years ago

Draw a picture that represents 3x50=150?

10 years ago

Suppose that 20 workers were required in 2010 to produce 120,000 bushels of wheat on a 1,000-acre farm. a. What is the average output per acre? (?) bushels per acre What is the average output per worker? (?) bushels per worker b. If in 2020 only 16 worker...

10 years ago

According to the CDC, 25 % of college students get the flu every year. (a) If 7 college students are selected at random? What is the probability that exactly 6 of them have the flu? (b) What is the mean and standard deviation for this distribution?

9 years ago

Two tourists went on a hike at dawn. One went from a to b and another one went from b to a. They met at noon but did not stop and continued walking maintaining same speed for the whole trip. One finished his hike at 4pm in B and another one came to A at 9...

7 years ago

Is "words are eaten" personification?

7 years ago

I need to write a real life word problem for X + 13 = -34

5 years ago

Evaluate the expression (3²)²+ 1

4 years ago

Hey i was wondering if you guys can help me with a question. Which of the following choices is true about models used in science? A.better technology rarely produces better models B.they behave and look exactly like the systems they mimic C.they are usual...

4 years ago

A state used to have a flat tax rate on individual income taxes. Recently the state implemented a progressive tax structured on individual income taxes. Predict the possible consequences of the implementation of a progressive tax structure? Lower-income i...

3 years ago

The cells are programmed to die and then they send signals to their membranes, which inform macrophages to come dispose of them. The macrophages engulf the apoptotic cells, allowing for the recycling of certain molecules. All of the cell parts are recycle...

17 years ago

ok... first of all, rise over run is when you are trying to find the slope of the line, or even two points. For instance, let's say you have these two points: (1,3) and (5,6) x's are the "run" and y's are the "rise" you know that rise/run = m = slope. Now...

17 years ago

The reflected ray is a ray of light which leaves the surface.

17 years ago

Although 16th birthday is not usually as special as the 18th birthday, we do still celebrate it in Korea. The legal drinking/driving age is 19. Valentines Day is usually big when the girls give the guys chocolates. Also, there is also such thing as the "W...

17 years ago

Yes. 18th birthday is usully more "valued" in a sense you have more freedom. 16th birthday - not so much. It's not like you can get a license or anything like that. Teens in Korea celebrate their 18th birthdays with their friends usually at a restaurant o...

17 years ago

1. y = 2x + 2 so in this case, the slope is 2. Perpendicular slope is a negative reciprocal, which means it would be... -1/2. 2. this is when you do a cube root of 8. You are asking yourself, what is the value of x for the equation, x^3 = 8. So you get x...

17 years ago

1. you are plugging in g(x) in place of x for f(x). So you get 3(2)-2. 2. no matter what number you put in for x for g(x), you will get 2. 3. same logic. plug in 5 in place of x, so you get h(5) = 4(5)

17 years ago

First, try to see if you can cancel out any of the variables by adding the equations. 4x+2y-1 also equals 4x+2y=1 (4x+2y=1)(2) = 8x+4y=2 now, add the two equations and see the y cancel out. 2x-4y=2 8x+4y=2 10x=4 x=4/10=2/5 Plug this number back into the e...

17 years ago

why do* I am talking about the cellular respiration here.

17 years ago

The hydrogen ions are pumped into the intermembrane space from the mitochondrial matrix. Oxygen captures the electrons in the very last step in the electron transport and adding electrons to that oxygen atom and two hydrogen ions form water. No. ATP synth...

17 years ago

Those molecules containing carbon atoms are known as organic compounds. It's a vital part of life - especially when we talking about living organisms. Biological diversity has its molecular basis in carbon's ability to form a huge number of molecules with...

17 years ago

Noncoding DNA sequences on homologous chromosomes exhibit small nucleotide differences- and introns account for this difference. RFLPs are scattered throughout genomes and it serves as a genetic marker for particular location in the genome. A single chang...

17 years ago

A heterotroph

17 years ago

Thank you so much, DrBob! I appreciate it!

17 years ago

That makes a lot of sense. Thank you!

17 years ago

I figured it out. All you need to do is use Wnet = Wforce + Wspring = Kf - Ki twice. Once for the entire displacement Kf - Ki = 0 and once for half way where Kf - Ki = 2.4. Both times you will have a k(spring constant term) in the equation and if you solv...

15 years ago

did you get number 9?!!

15 years ago

nvm i got the answers

15 years ago

how do you properly write the answer?

15 years ago

as lim goes to 4

15 years ago

i got -2 but i don't know what the theorem is called

15 years ago

i meant what happens as v goes to c-

15 years ago

i already know this rule but im still having trouble solving it

15 years ago

5/2 because 60 divided by 12 = 5 24 divided by 12 = 2

14 years ago

5.1m

9 years ago

764

8 years ago

Thanks!

7 years ago

24

4 years ago

How i interpreted C is its either saying it's for systems that are to easy to get in that case the answer would be wrong or it's saying it's to make harder systems to get easier in that case the answer would be correct

4 years ago

두 해양 판이 충돌하면 하나의 해양 판이 결국 다른 판 아래로 섭입됩니다. 한 판이 다른 판 아래로 미끄러지는 곳을 '섭입대'라고 합니다. 섭입판이 맨틀로 내려가면서 점차 가열되고 있는 베니오프 영역이 형성됩니다. (When two oceanic plates collide one oceanic plate...

3 years ago

두 해양 판이 충돌하면 하나의 해양 판이 결국 다른 판 아래로 섭입됩니다. 한 판이 다른 판 아래로 미끄러지는 곳을 '섭입대'라고 합니다. 섭입판이 맨틀로 내려가면서 점차 가열되고 있는 베니오프 영역이 형성됩니다.

3 years ago