How does gravity turn out to be $32\text{ ft/s}^2$ in this problem?

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A baseball is hit from 3ft above home plate with an initial velocity $v(0)=(80,80) \text{ ft/s}$. Neglect all forces other than gravity. How far does the ball travel horizontally? Does the ball clear a $20\text{ ft}$ fence that is $380\text{ ft}$ from the home plate?

Step 1: Find the velocity vector from the acceleration vector. The acceleration vector is found by the gravity $g = 32\text{ ft/s}^2$, which is $a(t) =(0, 32)$. By integrating $a(t)$ and using $v(0)$, we find $v(t) =(80, 32t + 80)$.

I don't understand how they went from the usual $9.8\text{ ft/s}^2$ to $32$... Can someone explain this to me?