What is the volume in cubic yards of a green house that is 50 yards long, 20 feet wide, and 10 feet high

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.

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Sanjay solved the equation below. which property did he use to determine that 7x+42=42 is equivalent to 7(x+6)=42 7x+42=42 7x=0 x=0