Jason has the following averages in his math class: Homework Avg.: 80,

Quiz Avg.: 84,

Test Avg.: 74,

Final Exam: 60.

The teacher weights Homework at 20%, Quizzes at 30%, Tests at 40%, and the Final Exam at 10%. How many points did he earn from the QUIZ category towards this final average?

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.