Mattt's parents pay him $5.50 for each half hour he babysits his sister, plus a $2 tip. if matt made $18.50, for how long did he babysit?

After t seconds, a ball tossed in the air from the ground level reaches a height of h feet given by the equation h = 144t-16t^2. after how many seconds will the ball hit the ground before rebounding?

Akid's pool is cylindrical and has a radius of 5 feet and a height of 2 feet. if a cubic foot holds about 7.48 gallons of water, how many gallons of water does the kid's pool hold? 21 gallons 52.3 gallons 1,174,4 gallons 157 gallons

The coverage of a base station of a telecommunication company forms a disk with a radius of (kilometers). let be the distance of a cellphone from a base station. assume that the location of cellphones in use are randomly uniformly distributed within the disk. calculate the mean and variance for the random variable.