Hi avatar- just done it in my head and I agree with 10 days for part (1). Initially I got exactly 10 days, but i was going off teh clock times not teh real time.
I did:
3 mins difference every hour.
72 mins gaps after 24 hours (1 day).
360 mins (6 hour) gap after 5 days
12 hour gap after 10 days.
I suppose clock A has gained 240 hours after 10 days. So it shows 4.00 am
Can't be bothered with last bit- oh I suppose it's 3 x as much (assuming it's a 12 hour clock not a 24 hour clock). So that's 12.00 noon on the 30th Jan