The number of students who enroll in a psychology course is a Poisson random variable with mean 105. The professor in charge of the course has decided that if the number enrolling is 119 or more, the course will be taught in two sections, whereas if fewer than 119 students enroll, the students will be all taught together in a single section. What is the probability that the professor will have to teach two sections?

Find the volume of the solid obtained by rotating the region enclosed by the curves y=1x and y=7^-x about the x-axis. (use symbolic notation and fractions where needed.) volume =

Select the correct answer what is the 10th term of the geometric sequence 3,6, 12, 24,48 a. 512 b. 3,072 c. 768 d. 1,536

Suppose we have a set of small wooden blocks showing the 26 letters of the english alphabet, one letter per block. (think of scrabble tiles.) our set includes 10 copies of each letter. we place them into a bag and draw out one block at a time. (a) if we line up the letters on a rack as we draw them, how different ways coukl we fill a rack of 5 letters? (b) now suppose we just toss our chosen blocks into a pile, and whenever we draw a letter we already have, we put it back in the bag and draw again. how many different piles of 5 blocks could result? possible? piles will contain at least one repeated letter? (c) if we draw out 5 blocks wit hout looking at them, how many different piles are (d) if we draw out 5 blocks without looking at them, how many of the possible 2. (4) consider the following formula. 12 give two different proofs, one using the factorial formulas and the other combina torial.