(30 POINTS) Elliott is standing at the top of a store escalator that leads to the ground floor below. The angle of depression from the top of the escalator to the floor is 36.84°, and the escalator is 15 feet long. How far is the top of the escalator from the ground floor? Round your answer to the nearest foot. 9 feet 12 feet 20 feet 36 feet Also i should add that i had this question before, but i got it incorrect because i was supposed to find the angle complementary to 36.84. The first time i got this question, i used cos 36.84 = x + 15.

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.