The number of bacteria in species A at time t is given by:

.
The number of bacteria in species B at time t is given by

You are asked to find N(t) which is the difference in the species at time t. Difference refers to the answer is a subtraction problem. Thus, we are asked to find N(t) = A(t)-B(t)
We subtract and obtain:

That is,

which is the last answer choice.
With respect to notation, it is common to denote an exponent using ^. So if we want to write

we can write "(.25t)^3"
Answer:
I think it is option 4, because it has the same scale. The height is 3 times as much as the radius.

Now, If the exponent was negative like you asked....
The probability of getting heads on the toss of a coin is 0.5. If we consider all possible outcomes of the toss of two coins as shown, there is only one outcome of the four in which both coins have come up heads, so the probability of getting heads on both coins is 0.25.
also is this for edge cause im doing the same lesson rn
What exactly are you asking? Can you maybe describe it more please?