Answer:
D
Step-by-step explanation:
The domain is the x value which in this case would be the hours of training


Cancel out the denominators.
(x+5)² + 18 = -30
(x+5)² = -30 - 18
(x+5)² = -48
The equation is impossible, we have a negative number.
There isn't a number that squared gives a negative number (the square is always positive).
√(x+5)² = +/- √-48
x+5 = +/- √-48
IMPOSSIBLE
You can write the result in imaginary numbers
x+5=+/- 4i√3
Twelve million threehundred and seventy five thousand ans three
Sorry if im wrong but i am pretty sure that is 266
The given function is

The general form of the cosine function is

a is the amplitude
2pi/b is the period
c is the phase shift
d is the vertical shift
By comparing the two functions
a = 4
b = pi
c = 0
d = 1
Then its period is

The equation of the midline is

Since the maximum is at the greatest value of cos, which is 1, then

Since the minimum is at the smallest value of cos, which is -1, then

Then substitute them in the equation of the midline

The answers are:
Period = 2
Equation of the midline is y = 1
Maximum = 5
Minimum = -3