Fuel flows into a storage tank at a rate given by
R(t)=3e−0.2t gallons per minute,
for 0≤t≤10 minutes. If the tank initially contains 50 gallons of fuel, which of the following is closest to the amount of fuel in the tank after 10 minutes?
(a) 54 gallons
(b) 13 gallons
(c) 63 gallons
(d) 38 gallons