I dont under stand this

Arectangular exercise mat has a perimeter of 36 feet the length of the mat is twich the width writeand solve an equation to determine the length in feet. of the mat then find the area in square feet of the mart

One of the inventors of integrated circuits observed that the number of transistors that fit on an integrated circuit will double every 24 months. what type of relationship most appropriately models this situation?

Solve the triangle. a = 21°, c = 105°, c = 5