
Dan O. answered 11/08/20
Perfect score on Math SAT / GRE; 5 yrs experience as a AP Calc teacher
First, we want to find the antiderivative (integrate) of r(t), which we can call h(t).
The units for h(t) would just be ounces of honey.
The antiderivative of r(t) is:
h(t) = (4 / -.35)e^(-.35t) + c
h(t) = -11.4286e^(-.35t) + c
Using initial condition, h(0) = 3, we can find c.
3 = -11.4286e^(-.35(0)) + c
3 = -11.4286 + c
c = 14.4286
Therefore,
h(t) = -11.4286e^(-.35t) + 14.4286
Because t is in minutes, we need to convert t = 4 seconds into minutes.
4 / 60 = 1/15 minutes
h(1/15) = 3.26358 ounces of honey