There are 2,100 bacteria in a circular petri dish. the dish has a radius of 40 millimeters. what is the approximate population density? (use 3.14 for π)

area of a circle = πr2
0.02 bacteria per square millimeter
0.42 bacteria per square millimeter
2.39 bacteria per square millimeter
52.5 bacteria per square millimeter

Angela is buying a dress that is on sale for 20% off. if the original price of the dress is $40.00, how much money is angela saving on the dress? a. $0.80 b. $3.20 c. $32.00 d. $8.00

Kayla and alberto are selling fruit for a school fundraiser. customers can buy small boxes of grapefruit and large boxes of grapefruit. kayla sold 3 small boxes of grapefruit and 1 large box of grapefruit for a total of $65. alberto sold 1 small box of grapefruit and 1 large box of grapefruit for a total of $55. what is the cost each of one small box of grapefruit and one large box of grapefruit?

To decrease an amount by 16% what single multiplier would you use