9514 1404 393
Answer:
8 seconds
Step-by-step explanation:
Your answer is the time interval at which the projectile is at or above ground level.
The way I read the question, it is asking for the value of t when the projectile hits the ground. It is 8 (seconds). My answer to this question would be 8, or 8 seconds.
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Comment
We cannot tell whether the answer is intended to include units, or not. The usual clues are missing here.
