100 points for who answers first
3(m + 5 + 9m)
part a: write two expressions that are equivalent to the given expression. (3 points)
part b: show that one of your expressions in part a is equivalent to the given expression using algebraic properties. explain which properties you used. (4 points)
part c: show that your other expression from part a is equivalent to the given expression by substituting a number for m. (3 points)

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.