29^2+29*21 chia hết cho 50

An engineer scale model shows a building that is 3 inches tall. if the scale is 1 inch = 600 feet, how tall is the actual building?

For a function f(x), a) if f(7) = 22 then f^-1(22) = b) f^-1(f(c)) =

Which number can each term of the equation be multiplied by to eliminate the decimals before solving? 5.6j- 0.12=4+1.1j