Someone help me solve this please

The perimeter of a movie screen is 54 meters. the screen is 18 meters wide. how tall is it?

Tim's phone service charges $26.39 plus an additional $0.21 for each text message sent per month. if tim's phone bill was $31.64, which equation could be used to find how many text messages, x, tim sent last month?

Simplify (2^5/3^2)^4 a. 2^20/3^8 b. 2^9/3^8 c. 8^5/12^2 d. 2/3^2