A radioactive substance decays exponentially. A scientist begins with 160 milligrams of a radioactive substance. After 26 hours, 80 mg of the substance remains. How many milligrams will remain after 43 hours?

Before simplifying, how many terms are there in the expression 2x - 5y + 3 + x?

{0,1,2,3,4,5,6,20,21,22,23,24,25} the distribution is considered to be: skewed the right, skewed the left, not skewed?

Is the product of two rational numbers irrational or rational? first, make a hypothesis by multiplying two rational numbers. then, use variables such as x=a/b and y=c/d and the closure property of integers to prove your hypothesis.