A balloon carring a stone is moving vartically upward with velocity `12 m//s`. When the balloon is at height `64 m`, the stone is dropped. After how much time and with what velocity will it strike the ground?

Explanation

To solve the problem of the stone dropped from the balloon, we can break it down into steps:

### Step 1: Understand the initial conditions
The balloon is moving upward with a velocity of \(12 \, \text{m/s}\) when the stone is dropped from a height of \(64 \, \text{m}\). When the stone is released, it has the same upward velocity as the balloon, which is \(12 \, \text{m/s}\).

### Step 2: Determine the initial velocity of the stone
Since the stone is dropped from the balloon, its initial velocity (\(u\)) at the moment of release is:
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