Walking across a bridge, a tourist throws a penny into the water below. The penny's height above the water in meters, p(x), depends on the time in seconds after throwing, x, and can be modeled with the function p(x) = -16x2+ 7x + 15. Approximately how many seconds after being thrown will the penny hit the water? 0.2 seconds 15.8 seconds 1.2 seconds 15 seconds​

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Use the frequency distribution, which shows the number of american voters (in millions) according to age, to find the probability that a voter chosen at random is in the 18 to 20 years old age range. ages frequency 18 to 20 5.9 21 to 24 7.7 25 to 34 20.4 35 to 44 25.1 45 to 64 54.4 65 and over 27.7 the probability that a voter chosen at random is in the 18 to 20 years old age range is nothing. (round to three decimal places as needed.)