Greye wants to tip the server at a restaurant more than 15%. If Greye’s bill was $30.00 before the tip is applied, which inequality can he solve to find an amount, in dollars, he can give the server?

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.