Whats (8.5×.3×10^3) in scientific notation

Write a story that matches with the expression 42x-5 pls hurry

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a.m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?

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