Simplify the mathematical expression to determine the product or quotient in scientific notation round so the first factor goes to the tenth place

Bruce is getting materials for a chemistry experiment his teacher gives him a container that has 0.25 liter of liquid in it.bruce need to use 0.4 of this liquid for the experiment. how much liquid will bruce use?

Pls me this is due today and i need i will make brainliest if you me answer correctly and i will report if you try to give me a dumb answer.

What are the constants in this expression? -10.6+9/10+2/5m-2.4n+3m