Use the equation for variance below, along with the given data set, to answer the following questions. Sigma squared = StartFraction (x 1 minus mu) Squared + (x 2 minus mu) squared + ellipsis + (x N minus mu) squared Over N EndFraction What does the numerator evaluate to? What does the denominator evaluate to? The variance equals:

Parabolas y=−2x^2 and y=2x^2 +k intersect at points a and b that are in the third and the fourth quadrants respectively. find k if length of the segment ab is 5.

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.

18 16 11 45 33 11 33 14 18 11 what is the mode for this data set