Math pls help and thanks​

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.

What is the measure of angle lkj ? round to the nearest whole degree

The manager at gabriela's furniture store is trying to figure out how much to charge for a book shelf that just arrived. the book shelf was bought at a wholesale price of $ 1 4 7 . 0 0 $147.00, and gabriela's furniture store marks up all furniture by 6 0 % 60%. at what price should the manager sell the book shelf?