a city’s temperature is modeled as a normal random variable with mean and standard deviation both equal to 10 degrees celsius. what is the probability that the temperature at a randomly chosen time will be less than or equal to 15 celsius? let y = 1 if the temperature is less than or equal to 15 celsius, and y = 0 otherwise. find the variance of y

Simba travel agency arranges trips for climbing mount kilimanjaro. for each trip, they charge an initial fee of \$100$100 in addition to a constant fee for each vertical meter climbed. for instance, the price for climbing to the shira volcanic cone, which is 30003000 meters above the base of the mountain, is \$400$400. let f(d)f(d) denote the fee of a trip ff (measured in dollars) as a function of the vertical distance climbed dd (measured in meters). write the function's formula. f(d)=