A speedboat starts from rest and accelerates at +2.41 m/s2 for 5.14 s. At the end of this time, the boat continues for an additional 6.24 s with an acceleration of +0.451 m/s2. Following this, the boat accelerates at -0.551 m/s2 for 7.51 s. (a) What is the velocity of the boat at t = 18.89 s? (b) Find the total displacement of the boat.