Answer
a. 5.3 m/s.
b. 1.8 m/s.
Work Step by Step
a. The definition of average speed is the total distance over the time. The distance traveled is 38 m + 0.5(38 m) = 57 m.
$$\frac{57 m}{9.0 s + 1.8 s} = 5.3 m/s$$
b. The displacement is 19 m.
$$\frac{19 m}{9.0 s + 1.8 s} = 1.8 m/s$$
