The cost, in dollars, per watt of solar energy is a function of the number of years since 1977, t. The cost could be modeled by an exponential function f. Here is the graph of the function. image

What is a reasonable domain for the function?

A.
t > 0

B.
t < 80

C.
[0, 10]

D.
[0, 80]

Evaluate-27 ^4/3/8 a) - 81/16 b) 81/16 c) 16/81

I'm confused on this could anyone me and show me what i need to do to solve it.

Assume that females have pulse rates that are normally distributed with a mean of mu equals 72.0 beats per minute and a standard deviation of sigma equals 12.5 beats per minute. complete parts (a) through (c) below. a. if 1 adult female is randomly selected, find the probability that her pulse rate is between 65 beats per minute and 79 beats per minute. the probability is? b. if 16 adult females are randomly selected, find the probability that they have pulse rates with a mean between 65 beats per minute and 79 beats per minute. the probability is? c. why can the normal distribution be used in part (b), even though the sample size does not exceed 30?