Answer
(a) $4A$ (b) $10A$
Work Step by Step
The period is the time it takes for a particle to go through one full cycle of oscillation. One full cycle for a mass oscillating requires the mass to move from $A$ to $-A$ and then back to $A$. This total distance is $2A+2A=4A$. Since the distance traveled in $T$ s. is $4A$, the distance traveled in $5T/2$ s. is $\frac{5}{2}(4A)=10A$.