Identify the number in the thousands period for 8,451,209.

need !

Can someone answer and tell me how to do this (will mark brainliest)

Afile that is 274 megabytes is being downloaded. if the download is 12.8% complete, how many megabytes have been downloaded? round your answer to the nearest tenth.

Awalker is already walking 5km per day and decides to increase this amount by 0.1km per day starting on 1st august. what distance will he be walking on 3rd august? b. is this an arithmetic sequence? explain your reasoning. c. what is the formula for the nth term?