If x, 30,24 and 16 are in proportion then find the value of x. ​

Antonio made a scale model of a building. the model's scale is 1 inch to 235 feet and its height is 3.5 inches. what is the exact height of the actual building? enter your answer in the box.

Evaluate the expression for the given value of the variable 2×(c2-5) for c=4

Given f(x)= 9x+1 and g(x)=x^3, choose the expression (f*g)(x)