The normal monthly temperatures (°F) for Omaha, Nebraska, are recorded below.
Month
Jan
Feb
Mar
Apr May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
1
2
3
4
5
6
7
8
9
10
11
12
21°
27°
390
52°
62°
720
770
740
65°
53°
Temp.
39°
25°
a. Write a sinusoidal function that models Omaha's monthly temperature variation.
b. Use the model to estimate the normal temperature during the month of April.