You're reviewing the campaigns of a new client who wants to better promote his child daycare facility to parents researching childcare on their mobile devices. currently, his ads include generic text about childcare. to optimize his ads for mobile, you might create an ad with:

When it is 4: 00 a.m. in halifax, it is 1: 00 p.m. in karachi, and when it is 9: 00 a.m. in karachi, it is 5: 00 a.m. in warsaw. mary left halifax to fly to karachi, but she accidentally left her watch on warsaw time. according to mary’s watch, she left halifax at 9: 40 p.m. on monday. the local time when she arrived at karachi was 3: 00 p.m. tuesday. how long was mary’s flight? a. 9 hours, 20 minutes b. 13 hours, 20 minutes c. 14 hours, 20 minutes d. 17 hours, 20 minutes