81 because 81 is a perfect square and 27 times 3 =81
You use sine, cosine, or tan
(f+g)(x) = 2^x + 5x + 3x - 5
(f+g)(x) = 2^x + 8x - 5
answer
C. 2^x + 8x - 5
Answer:

Using this condition we got:

And solving for b we got:

So then our linear function is given by:

Where y is the amount of fluid left and x the number of hours ellapsing
Step-by-step explanation:
We want to set up a linear function like this one:

Where y is the amount of fluid left, m the slope and b the initial amount. From the info given we know thatm = -300. And we also have the following condition:

Using this condition we got:

And solving for b we got:

So then our linear function is given by:

Where y is the amount of fluid left and x the number of hours ellapsing
Answer:
The answer would be, both A. and B.