Aprofessor must randomly select 4 students to participate in a mock debate. there are 20 students in his class. in how many different ways can these students be selected, if the number of selections does not matter?

Aball is thrown from a height of 139 feet with an initial downward velocity of 15 ft/s. the ball's height h (in feet) after t seconds is given by the following. h=139-15t-16t^2 how long after the ball is thrown does it hit the ground? round your answer(s) to the nearest hundredth. (if there is more than one answer, use the "or" button.) t =

How to simply and write the answer n a whole number

What is the simplified form of square root of 400 to the 100th power ?