Element X is a radioactive isotope such that every 5 years, its mass decreases by half. Given that the initial mass of a sample of Element X is 590 grams, how much of the element would remain after 23 years, to the nearest whole number?

An episode of a television show is 60 minutes long when it originally airs with commercials. on a dvd without commercials, the episode is only 417 minutes long. how many1-minute commercials did the episode include when it originally aired? write and solve an equation to justify your answer.

Ten times the square of a non-zero number is eqaul to ninety times the number

2.5 milligrams is equivalent to how many grams