What is the unit rate $11.99 for 15 lbs

Find the nonpermissible replacement for binthis expression. b2/5b +5

Solve the triangle. a = 21°, c = 105°, c = 5

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