Can anyone answer this with workings pls?

0if x and y vary inversely and y=6 as x=7, what is the constant of variation?

Describe how making an ‘and’ compound sentence effects your solution set

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 .