8 x 10-3 is how many times as great as 4 x 10-6? A. 2 x 10-3
B. 2 x 10
C. 2 x 10-9
D. 2 x 103

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