Exercise 3.62. A little boy plays outside in the yard. On his own he would come back inside at a random time uniformly distributed on the interval [0, 1]. (Let us take the units to be hours.) However, if the boy is not back inside in 45 minutes his mother brings him in. Let X be the time when the boy comes back inside (a) Find the cumulative distribution function F of X (b) Find the mean E(X) (c) Find the variance Var(X) Hint. You should see something analogous in Examples 3.20 and 3.38.

Marco is studying a type of mold that grows at a fast rate. he created the function f(x) = 345(1.30)x to model the number of mold spores per week. what does the 1.30 represent? how many mold spores are there after 4 weeks? round your answer to the nearest whole number. 1.30 represents the number of mold spores marco had at the beginning of the study; 985 mold spores 1.30 represents the number of mold spores grown in a given week; 448 mold spores 1.30 represents the 30% rate of weekly growth; 345 mold spores 1.30 represents the 30% rate of weekly growth; 985 mold spores