Construct a polynomial function with the following properties: third degree, only real coefficients, −1 and 2+i are two of the zeros, y-intercept is −5.

The average daily maximum temperature for laura’s hometown can be modeled by the function f(x)=4.5sin(πx/6)+11.8 , where f(x) is the temperature in °c and x is the month. x = 0 corresponds to january. what is the average daily maximum temperature in may? round to the nearest tenth of a degree if needed. use 3.14 for π .