PLEASE HELP
which mapping diagram represents a function from x → y

Ten times the square of a non-zero number is eqaul to ninety times the number

Is the power produced directly proportional to the wind speed, give reasons for your answer?

James wants to promote his band on the internet. site a offers website hosting for $4.95 per month with a $49.95 startup fee. site b offers website hosting for $9.95 per month with no startup fee. for how many months would james need to keep the website for site a to be a better choice than site b?