A model rocket is launched directly upward at a speed of 28 meters per second from a height of 12 meters. The function f(t) = - 4.9t ^ 2 + 28t + 12, mo models the relationship between the height of the rocket and the time after launch. in seconds When seconds after launch will the rocket hit the ground? Do not round until the final answer. Then round your answer to two decimal places. Provide your answer below:

(b) suppose that consolidated power decides to use a level of significance of α = .05, and suppose a random sample of 100 temperature readings is obtained. if the sample mean of the 100 temperature readings is x⎯⎯ = 60.990, test h0 versus ha and determine whether the power plant should be shut down and the cooling system repaired. perform the hypothesis test by using a critical value and a p-value. assume σ = 5. (round your z to 2 decimal places and p-value to 4 decimal places.)