I can’t figure out the red part please help much appreciated

The rumpart family is building a new room onto their house. the width of the new room will be 16 feet. the length of the room will be 4% greater than the width. write an expression to find the length of the new room. what will be the area of this new room?

Find the number of liters in 12.8 gal of gasoline. round to the nearest hundredths

Evaluate cos2θ for cosθ = square root of 3/2