i need help. not saying these are right, i just tried my best, could someone check them for me? (NOT ALL ARE ANSWERED)

1. (-5)^-1
A. - 1/5 **********
B. -5
C. 5
D. 1/5

2. (-8.3) ^0
A. 1
B. -1
C. 0
D. -8.3 **********

3. -1/a^-2
A. -a^2
B. -2/a
C.-2a
D. a^2 **********

4. 4^6 * 4^3
A. 4^9 **********
B. 4^18
C. 12^9
D. 64^9

5. (3)^10 (3)^-9
A. 3
B. 1/3
C. 9^-90 **********
D. 9

6. (y^6)^2
A. 2y^12
B. y^12 **********
C. y^8
D. y^36

7. (6q^6)^-4
A. 6q^1296
B. 1296q^2
C. 1/1296 q^24
D. 6q^-24 **********

8. What is the value of 11x^-3 y^-1 for x= -1 and y=2
A. -2/11
B. -22
C. -66
D. -11/2
(yikes i dont know this one...)

9. (t^-4)^-9 t^2
A. t^26
B. t^-26 **********
C. t^38
D. t^-38

10. (4/7y^5) ^2
A. 8 / 14y^10
B. 16/ 49 y^25
C. 16/9^10
D. 8/14 y^25

11. Determine if the number 3.14*10^-6 is written in scientific notation. If not, explain.
A. Yes; the number is written in scientific notation **********
B. No; the first number is not a number between 1 and 10
C. No; it is not written as a number times a power of 10

There is 23 questions overall but I will submit in the rest once I try to finish and see if anyone is able to help me here.

3 answers

#1 , yes
#2
sorry, pressed submit too soon

#2 , no, anything ^0 = 1
#3, no, -1/a^-2 = -1(a^2) or -a^2
#4 yes
#5 ,no , same kind as #4, why did you go off very strange here?
(3)^10 (3)^-9 = 3^1 or 3
#6 yes
#7 no, (6q^6)^-4 = (6^-4)(q^6)^-4
= (1/1296)(q^-24)
=1/(1296q^24) which is C
#8 11x^-3 y^-1 = 11(1/x^3)(1/y) = 11(1/(-1)^3 )(1/2) = 11(-1)(1/2) = -11/2
#9 no , (t^-4)^-9 t^2 = t^36 t^2= t^38
#10 ??? , very easy (4/7y^5) ^2 = (16/49)y^10
#11 yes,

4/11 is not close to competency. Looks like somebody has to spent
some more time on this.
Correct answer:

1.

4.

6.

and

11

Wrong answers:

2. ( - 8.3 )⁰ = 1

Any number to zero power is equal one.

3.

a⁻² = 1 / a²

so

- 1 / a⁻² = - 1 / ( 1 / a² ) = - 1 ∙ a² = - a²

5.

aᵐ ∙ aⁿ = aᵐ⁺ⁿ

3¹⁰ ∙ 3⁻⁹ = 3¹⁰⁻⁹ = 3¹ = 3

7.

( aᵐ )ⁿ = aᵐ ⁿ

( 6 q⁶ )⁻⁴ = 6⁻⁴ ∙ ( q⁶ )⁻⁴ = 1 / 6⁴ ∙ q²⁴ = 1 / 6⁴ ∙ q²⁻⁴ = 1 / 1296 ∙ 1 / q²⁴ = 1 / 1296 q²⁴

8.

11 x⁻³ ∙ y⁻¹ = 11 ∙ 1 / x³ ∙ 1 / y¹ = 11 / x³ ∙ y

Put x = - 1 and y = 2 in this expression

11 / (- 1)³ ∙ 2 = 11 / (- 1) ∙ 2 = 11 / - 2 = - 11 / 2

9.

( t⁻⁴ )⁻⁹ ∙ t² = ( t )⁻⁴ * ⁻⁹ ∙ t² = t³⁶ ∙ t² = t³⁶⁺² = t³⁸

10.

( 4 / 7 y⁵ )² = ( 4 / 7 )² ∙ ( y⁵ )² = 4² / 7² ∙ y⁵*² = 16 / 49 ∙ y¹⁰