Meanderings: Nautical maths challenge

As you may have gathered from Lauren's post, I had an excellent birthday today. I'll post more about that later, but for now I wanted to give the mathematically inclined of you a little challenge. I dreamed this up for the kids, but it was a little too challenging for them. See how you fare. Feel free to post your answers as comments to this post. At some point I will post the ~~correct~~ expected answers...

This challenge pretty accurately reflects what I spent the last morning of my 45th year doing:

The situation:

Giles goes for a row up the Mitchell River. In still water Giles rows at a speed of 2 knots (=2 Nautical Miles per hour), however the Mitchell River has a current with a speed of 1 knot flowing downstream. Giles rows for a distance of 1.5 Nautical Miles upstream (from the point where we got stuck due to shallow water to the point we expected we would get stuck due to low power lines crossing the river). He then returns to Meander (which remained anchored throughout this exercise).

The questions:

a) If Giles rowed continuously, without stopping, for his entire trip, how long did it take him?
b) How far, through the water, did Giles actually row?
c) If Giles stopped rowing (and drifted) for 30 minutes taking photographs, how long did the trip take him?
d) Does the answer to c) depend on whether he took the photos during his upstream or downstream journey and, if so, how much difference does this decision make to the duration of his trip?

Ahh, the things some of us think about while we row...

I'll finish with a couple of the photos that I took while drifting back down the river and, no, that is not a hint, other factors are far more important to photography, such as what the sun and wind were doing at the time, than the possibility that the rowing time might be increased. I actually spent about an hour taking photos, half an hour on the way up, and half an hour on the way back down again...

And, yes, thank you, I did have a very pleasant row.