Use the following to construct a function that will model the amount of Cobalt-60 remaining after t years, from an initial amount of 10 kg. Q(t) = Pen Where Q(t) describes the amount of Cobalt-60 remaining after t years from an initial quantity of P kg. 1. Q(t) = 10^60^(t) 2. How long (in years) will it take for the amount of Cobalt-60 remaining to reach 4 kg?