HELP

Aplane flies around trip to philadelphia it flies to philadelphia at 220 miles per hour and back home with a tailwind at 280 miles per hour if the total trip takes 6.5 hours how many miles does the plane fly round trip

45 was divided by a power of ten to get 4.5. what power of ten was it divided by? people 4.5

The standard deviation for a set of data is 5.5. the mean is 265. what is the margin of error?