Donny is measuring the angles of a triangle. he measures the first two angles and gets 30° and 100°. how could he find the measure of the third angle? a) subtract 100 and 30 from 180 since the three angles should sum up to 180°. b) subtract 100 and 30 from 360 since the three angles should sum up to 360°. c) add 100 and 30 since the third angle should be the sum of the first two angles. d) add 100 and 30 and then double it since the third angle should be twice the sum of the first two.

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.

1. if events a and b are non-overlapping events, how do you find the probability that one or the other occurs? 2. what does it mean if p(a or b) equals 1?

The value, v, of kalani’s stock investments over a time period, x, can be determined using the equation v=750(0.80)^-x. what is the rate of increase or decrease associated with this account? 20% decrease 20% increase 25% decrease 25% increase