Add 5 hours 43 minutes 52 seconds and 1 hour 22 minutes 12 seconds.

Answer: C. 7 hours 06 minutes 04 seconds

Step 1 : Add seconds
52 +12 = 64 second ,we know 60 second = 1 minute so, write 04 second . Carry 1 minute to minutes.
Step 2 : Add minutes
43 + 22 = 65 minute , we know 60 minute = 1 hour so, write 06 minute . Carry 1 hour to hours .
Step 3 : Add hours
Add it normally so answer = 7 h 06 min 04 sec

Answering after opening this box earns no Practice Points.