A model rocket is launched into the air with an upward velocity of 64 ft/s. Its height h in feet after t seconds is given by the function h=-16t²+64t+1. How many seconds will it take the rocket to reach it's maximum height?
A dolphin can swim 8 miles downstream on a river in 20 minutes. It takes 30 minutes for the dolphin to go upstream the same 8 miles. What is the current rate of the river?
At The World is Round High School, there are 221 sixth graders. 61 of the students are members of the science club, 35 are in the math club, and 24 are in both. How many students are in neither club?
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