Which is the sum of 3.15 × 107 + 9.3 × 106? Write your answer in scientific notation. A 4.08 × 106 B 4.08 × 107
C 0.408 × 108 D 40.8 × 106

Find an equation of the line perpendicular to the graph of 28x-7y=9 that passes through the point at (4,1)

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

Eden has a part time job. she is paid ? 7.20 an hour the week she worked 18 and a half hours how much is she paid