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Jamie is hiking up a small mountain. he climbs up at a constant rate of 300 feet/hour until he reaches the peak at 1,500 feet. after that, he hikes down at the same rate to the base of the mountain. the equation that models jamie’s elevation, e, after t hours is e = . jamie’s elevation will be 600 feet after hours and after hours.

The average number of vehicles waiting in line to enter a parking lot can be modeled by the function f left parenthesis x right x squared over 2 left parenthesis 1 minus x right parenthesis endfraction , where x is a number between 0 and 1 known as the traffic intensity. find the rate of change of the number of vehicles waiting with respect to the traffic intensity for the intensities (a) xequals0.3 and (b) xequals0.6.

Aball is thrown from a height of 139 feet with an initial downward velocity of 15 ft/s. the ball's height h (in feet) after t seconds is given by the following. h=139-15t-16t^2 how long after the ball is thrown does it hit the ground? round your answer(s) to the nearest hundredth. (if there is more than one answer, use the "or" button.) t =