Can someone help with both questions 19 & 20

19.

h=0, the result is 1000×2⁰ = 1000

this is the population of bacteria the excitement started with at the very beginning.

h=-3, the result is 1000×2-³ = 1000/(2³) = 1000/8 = 125

this is a calculation 3 hours backwards from the very start of the experiment, saying that if we started the experiment 3 hours earlier, this would have had to be the starting population of the bacteria so we would arrive at the same amount of population at any given time (value of h).

20.

D 25x⁶

Step-by-step explanation:

for 19 there is not more explanation. it is all ashtray in the answer.

for 20 we see that we are dealing with a square, so ask 4 sides have the same length.

one side is 5x³.

the area of a square is simply side².

so, here (5x³)² = 25x⁶

i believe the answer is c.