Start: 10: 45 a. m.
end: 11: 15 a. m.

what is the elapsed time?

30 minutes

Step-by-step explanation:

This is because from 10:45 to 11:00 is 15 minutes and then another 15 minutes is 11:15 which adds up to 30 minutes and that tells you how much time has passed from 10:45 to 11:15

30 minutes

Step-by-step explanation:

We can break down how to find elapsed time using a number line.  We write 10:45 on one side and 11:15 on the other.  Then we do a sort of guess, check, revise until you get the elapsed time.

if you are saying purchasing 3 social media ads and one newspaper ad counts as one purchase then there are:

6 purchases

if you are asking how many of each then:

18 social media ads

6 newspaper ads