Half-life of Po-210 is 140 days. If the initial mass of the sample is 5 kg, how much will remain after 420 days.

At 6 1/2 cents per pound of string beans how much does 7 pounds cost

Asandwich shop has 18 tables. each table seats up to 4 people. to find the greatest number of people that can be seated, you can solve p4 ≤ 18. which step is the best way to solve the inequality? plz asap i repeat plz

Whats four fifths to the first power