An element with a mass of 650 grams decays by 13.2% per minute. To the nearest minute, how long will it be until there are 220 grams of the element remaining?

Serena is making an experiment. for that, she needs 20 grams of a 52% solution of salt. she has two large bottles of salt water: one with 40% and the other with 70% of salt in them. how much of each must she use to make the solution she needs? i am in need of