Round 12,685 to the nearest thousands

Aculture started with 3000 bacteria. after 5 hours it grew to 3900 bacteria. predict how many bacteria will be present after 9 hours

Amanda went into the grocery business starting with five stores. after one year, she opened two more stores. after two years, she opened two more stores than the previous year. if amanda expands her grocery business following the same pattern, which of the following graphs represents the number of stores she will own over time?

An airplane travels at an unknown elevation before it descends 3 miles to an elevation of 15 miles. find the elevation of the plane before its descen.