**Given:** | | ** A projectile is launched upward at a velocity of 390 ft/sec on Earth. The projectile starts at ground level.** |

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**Find:** | a) | Write the function that describes the height of the projectile with respect to time.
h(t) = t^{2} + t + |

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| b) | At what time does the projectile reach the maximum height? [Round your answer to the nearest tenth.]
seconds |

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| c) | Determine the maximum height of the projectile. [Round the answer to the nearest foot.]
feet |

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| d) | At what time does the projectile reach ground level? [Round your answer to the nearest tenth.]
seconds |