Acontrolled experiment is designed to test
a. control
b. hypothesis
c. theory
d. prototype

B. Hypothesis That is because when doing an experiment one trying to find out whether the hypothesis is true or false.

The sun produces 3.9 ⋅ 10^33 ergs of radiant energy per second.
How many ergs the sun produce in 3.25 ⋅ 10^3 seconds

3.9 ⋅ 10^33 x 3.25 ⋅ 10^3
= (3.9 x 3.25)(10^33 x 10^3)
= 12.675 x 10^36
= 1.2675 x 10^37

answer
1.2675 x 10^37 ergs of radiant energy the sun produce in 3.25 ⋅ 10^3 seconds