(a) What was the impact speed when the lander touched the ground.
The impact speed is given by
![v=\sqrt[]{2gh}](https://img.qammunity.org/2023/formulas/physics/college/h5x6lakwlbvixuxzx7xrzzklyp6k7d0vvk.png)
Where g is the acceleration of gravity on the moon and h is the distance from the ground.
For the given case,
g = 1.62 m/s^2 = 5.31 ft/s^2
h = 4.3 ft
![v=\sqrt[]{2gh}=\sqrt[]{2\cdot5.31\cdot4.3}=6.76\; (ft)/(s)](https://img.qammunity.org/2023/formulas/physics/college/gtqje9ac8cjx1naoczy5r5mtuazhr6oxyk.png)
The impact speed of the lander is 6.76 ft/s
(b) How long did it take for the lander to drop the last 4.3ft
The time is given by

Therefore, it takes 1.27 s for the lander to drop the last 4.3 ft