[4] When designing a road, the radius of a curve is important to the safety of travelers in cars. The radius of the curve helps determine the maximum velocity that cars may travel while on the curve. The equation v = sqrt(2.5r) can be used to determine the maximum velocity a car can safely travel on an unbanked curve. The variable "prepresents the radius of the curve in feet. The variable "v" represents the maximum velocity in miles per hour that a car can safely travel when driving on the curve [a] What is the maximum velocity if the radius of the unbanked curve is 1440 feet? [b] What is the radius of the turn if the maximum velocity the car can travel is 50 mph?