Which algebraic expression represents the phrase “four times a number”?

With alll of except for the 2 that i did already

Suppose that the price p, in dollars, and the number of sales, x, of a certain item follow the equation 4 p plus 4 x plus 2 pxequals56. suppose also that p and x are both functions of time, measured in days. find the rate at which x is changing when xequals2, pequals6, and startfraction dp over dt endfraction equals1.5.

Asmall book publisher knows that 26 books weigh 41 lbs. how much do 40 books weigh?