Please help me! i'll mark brainliest:)

For f(x)=2x+1 and g(x)= x^2 -7, find (f•g)(x)

Explain how you can use the associative property to evaluate (7x50)x4.

Koji is installing a rectangular window in an office building. the window is 823 feet wide and 534 feet high. the formula for the area of a rectangle is a=bh. what is the area of the window? enter your answer as a mixed number in simplest form in the box. $$ ft2