Which polynomial is in standard form?

What is the simplified form of (3.25x10^3)(7.8x10^6) written in scientific notation?

Awater holding tank measures 105 m long, 50 m wide, and 8 m deep. traces of mercury have been found in the tank, with a concen- tration of 60 mg/l. what is the total mass of mercury in the tank? answer in units of kg.

James was playing a game with his friends. he won 35 points. then he lost 15, lost 40 and won 55. how did he come out