The table shows the normal daily high temperatures in Honolulu, Hawaii, $T$ (in degrees Fahrenheit) for month $t,$ with $t=1$ corresponding to January.
(a) Use a graphing utility to create a scatter plot of the data.
(b) Find a sine model for the temperatures.
(c) Use a graphing utility to plot the data and graph the model in the same viewing window. How well does the model fit the data?
(d) What term in the model you found in part (b) gives the average normal daily high temperature? What is the temperature?
(c) Use a graphing utility to describe the months in which the normal daily high temperature is above $86^{\circ} \mathrm{F}$