I’m stuck on how to do B, someone help please and thank you

Lois and clark own a company that sells wagons. the amount they pay each of their sales employees (in dollars) is given by the expression 12h+30w12h+30w where hh is the number of hours worked and ww is the number of wagons sold.

)a smart phone has dimensions of 4.9 inches (height), 2.3 inches (width) and 8.0 millimeters (depth). what is the volume of the smart phone in cubic centimeters? (1 in = 2.54 cm)

Find the values of y: 3y^3(y^2+ 2/3y)=0