2 and 3/4 is a mixed number and the decimal of it is 2.75
W + 3 = Ben's age or 3 + w = Ben's age, either way.
The given function is

with
t = time, hours
f = temperature, °C
Because the maximum and minimum values for the Sine function are +1 and -1 respectively,
The maximum value of f = 33 - 20 = 13.
The minimum value of f = -33 - 20 = -53.
The period, T, is given by

Answer:
Maximum: 13°; Minimum: -53°; period: 4 hours
C. is the answer because -159 is a rational number
Answer:
15 degrees less --> substract 15 degrees.
78.6 - 15 = 63.6 degrees