Astore is having a sale where school supplies are 30% off their original price. a backpack is on sale for $11.20. what was the original price for the backpack?

step-by-step explanation: a reaction is first order. if the initial reactant concentration is 0.0200 m, and 25.0 days later the concentration is 6.25 x 10-4 m, then its half-life is:

-4

step-by-step explanation:

do 6-10=

if u need it to be negative.