A bag contains 9 red marbles and 18 blue marbles. If a representative sample contains 2 red marbles, then how many blue marbles would you expect it to contain?

Aliter of water contains about 3.35 x 10^25 molecules. a certain river discharges about 2.9x 10^8 l of water every second. about how many molecules does the river discharge every minute? write your answer in scientific notation