The height of the pyramid is equal to 1/2 of the length of a side on the base. Which formla represents the volume of the pyramid?

The volume of the pyramid is a third of the volume of the prism which has the same base area and height as the pyramid. That is,

                          V = b²h / 3

Substituting the variables given,

                         V = (s²)(0.5s) / 3

Simplifying,

                         V = s³/6

they would have to work 32 hours.