Carlos is building three gardens, each the same size, in his backyard. Each garden is in the shape of a square with a 3-foot by 3-foot section removed from each of the four corners. One garden is shown below. A square with sides lengths of 16 feet. 3 by 3 feet squares are cut out of each corner of the larger square. What is the total area of all three gardens? 220 feet squared 256 feet squared 660 feet squared 768 feet squared

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.