Dunkin' Donuts data plot

Me! last question, and i'm stuck! write the algebraic expression that models the word phrase. the product of 2 divided by the number h and 8 more than the number k

Is this a polynomial function? i need to know asap

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 .