A speedboat starts from rest and accelerates at +2.01 m/s2 for 7.40 s. At the end of this time, the boat continues for an additional 5.80 s with an acceleration of +0.518 m/s2. Following this, the boat accelerates at ?1.49 m/s2 for 8.60 s.
(a) What is the velocity of the boat at t = 21.8 s?