:the variance of a series of numbers is the sum of the squares of their differences from the mean (average) of the numbers divided by the number of items in the series. variance is a common measure of risk. what is the variance of these investment returns? 10, 30, 20

Consider a bag that contains 220 coins of which 6 are rare indian pennies. for the given pair of events a and b, complete parts (a) and (b) below. a: when one of the 220 coins is randomly selected, it is one of the 6 indian pennies. b: when another one of the 220 coins is randomly selected (with replacement), it is also one of the 6 indian pennies. a. determine whether events a and b are independent or dependent. b. find p(a and b), the probability that events a and b both occur.

On the first of each month sasha runs a 5k race she keeps track of her times to track her progress her time in minutes is recorded in the table

Mr. rose asked his students to draw a quadrilateral with 4 unequal sides. draw an example of this kind of quadrilateral.