13. Suppose a city's temperature in degrees Fahrenheit t hours after 7:00 am is modeled by T(t) = 70 + 35 sin at 12 Find the city's average temperature during the period from 7:00 am to 7:00 pm. Round your answer to the nearest tenth of a degree. The average value of a function f(x) over [a, b) = _ 1 f(x) dr