Can anyone help I’ll give brainliest you don’t have to answer all of them!

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.

Helena lost her marbles. but then she found them and put them in 44 bags with mm marbles in each bag. she had 33 marbles left over that didn't fit in the bags.

Your company withheld $4,463 from your paycheck for taxes. you received a $713 tax refund. select the best answer round to the nearest 100 to estimate how much you paid in taxes.