1. **State the problem:** We want to find the time $t$ when the ball hits the ground. This means finding $t$ such that the height $h(t) = 0$.
2. **Write the height function:** The height above the ground after $t$ seconds is given by
$$h(t) = -16t^2 + 40t$$
3. **Set the height equal to zero to find when the ball hits the ground:**
$$-16t^2 + 40t = 0$$
4. **Factor the equation:**
$$t(-16t + 40) = 0$$
5. **Solve each factor for zero:**
- From $t = 0$, the ball is on the ground at the initial time.
- From $-16t + 40 = 0$, solve for $t$:
$$-16t + 40 = 0$$
$$-16t = -40$$
$$\cancel{-16}t = \cancel{-40} \Rightarrow t = \frac{40}{16}$$
6. **Simplify the fraction:**
$$t = \frac{40}{16} = \frac{5 \times 8}{2 \times 8} = \frac{5}{2} = 2.5$$
7. **Interpret the results:** The ball hits the ground at $t = 0$ (initial kick) and again at $t = 2.5$ seconds.
**Final answer:** The ball hits the ground after **2.5 seconds**.
**Answer choice:** (A) 2.5
Ball Hit Ground 7Ac05C
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