What goes inside each of these empty boxes?

Abox holds 500 paperclips. after a week on the teacher's desk 239 paperclips remained. how many paperclips were used?

The line plot below represents the number of letters written to overseas pen pals by the students at the waverly middle school. each x represents 10 students. how many students wrote more than 6 and fewer than 20 letters. a.250 b.240 c.230 d.220

Tom travels between the two mile markers shown and then finds his average speed in miles per hour. select the three equations that represent this situation.