Steve paid 10% tax on a purchase of $40. Select the dollar amount of the tax and the total dollar amount Steve paid on the number line.

The volume of a spherical hot air balloon v(r) = 4 3 ? r3 changes as its radius changes. the radius is a function of time given by r(t) = 3t. find the instantaneous rate of change of the volume with respect to t at t = 2.