What is the answer to: 2.8 x 10(3) x 3.07 x 10(5) (written in scientific notation) a) 86.0 x 10(8) b) 8.6 x 10(9) c) 859.6 x 10(9) d) 8.6 x 10(8)

Jackson earns $25 per hour as a tutor at the college library. he set a weekly spending budget of $130 each week and puts the remaining money in his savings account. how many hours must he work this week to have at least an extra $50 to put in his savings account