How to evaluate sin5pi/6? i know that sin5pi/6=sin(pi-pi/6),but what next? explain some details, !

If 10 men take 18 days to mow 60 acres of grass, how long will 15 men take to mow 80 acres?

Mat bought a phone for $100. he has to pay $30 per mouth. if he has paid $640 in total, how many mouth has he had the phone?

Which function can be used to model the monthly profit for x trinkets produced? f(x) = –4(x – 50)(x – 250) f(x) = (x – 50)(x – 250) f(x) = 28(x + 50)(x + 250) f(x) = (x + 50)(x + 250)