An environmental scientist tested a compost sample in the lab to find the number of bacteria it contained. The following output was given on her machine for one gram of compost.

Question

1.1E9

The mass of one cubic yard is about 765,000 grams. About how many bacteria would she expect to find in a cubic yard of the same compost?
A.
8.415 × 1014
B.
8.415 × 1013
C.
8.415 × 1012
D.
8.415 × 1015

Answer 1

D. 8.415 × 10^15

To find out how many bacteria would be in a cubic yard of the compost, you can simply multiply the number of bacteria in one gram by the number of grams in a cubic yard:

1.1E9 x 765,000 = 8.415 x 10^15

Therefore, the scientist would expect to find approximately 8.415 x 10^15 bacteria in a cubic yard of the compost.

Answer 2

Scientists are examining two different strains of a particular bacteria. The length of one strain of the bacteria measures 0.000000271 mm, while the length of the second strain measures 0.0000000763 mm. How much larger is the first strain than the second?
A.
3.473 × 10-7 mm
B.
3.473 × 10-15 mm
C.
1.947 × 10-8 mm
D.
1.947 × 10-7 mm

Answer 3

To find how much larger the first strain is than the second strain, we need to subtract the length of the second strain from the length of the first strain:

0.000000271 mm - 0.0000000763 mm = 0.0000001947 mm

Therefore, the first strain is 0.0000001947 mm larger than the second strain.

This is equivalent to:

1.947 x 10^-7 mm

So, the correct answer is:

D. 1.947 × 10^-7 mm