Perfect! Jerry's final velocity was $$5 \, \mathrm{m/s}$$. His initial velocity was $$2.5 \, \mathrm{m/s}$$. So, the change in velocity is $$\left(5 - 2.5\right) \, \mathrm{m/s}$$, and it takes $$2 \, \mathrm{s}$$ for that change. So, the acceleration is $$\frac{5 - 2.5}{2}$$.