Help me please ! Item 4
Aisha has a piece of string that she cuts into smaller pieces. This line plot shows the length of each piece. Juan has a piece of string that is 12 as long as Aisha's seventh-longest piece. (Note: The problem states the seventh-longest piece, not the seventh-longest length.)

How long is Juan's piece of string?

Enter your answer as a mixed number in simplest form by filling in the boxes.

in.

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.