Acyclist travels 39.6 feet per second. how many feet will he travel in 5 seconds? !

How do i do this activity, is appreciated

The following frequency table relates the weekly sales of bicycles at a given store over a 42-week period. value01234567frequency367108521(a) in how many weeks were at least 2 bikes sold? (b) in how many weeks were at least 5 bikes sold? (c) in how many weeks were an even number of bikes sold?

What is the number 321,000,000 in scientific notation? also what is the number? ?