Sorry for the delay in the answers. You've managed to get all but one of them!
1. T,S (DorsetSaint) – The sequence is just the initial letters of the question!
2. 312211, 13112221 (DorsetSaint) – Say the numbers out loud, individually. The first one is “one one”, the next is “two ones”, etc.
3. C,T (DorsetSaint). It’s not the obvious “WATER MELON”, but again, the initial letters of the question!
4. Which (DorsetSaint) – the answer is in the question!
5. APOLOGIES (David Tavener) – just remove the letters that make up the words “FIVE LETTERS”.
6. Eleven o’clock plus 2 hours is one o’clock (PelerinStJames, St Marlowe).
7. There are more of them (Clegthorpe).
8. There were only 3 fish (Clegthorpe) – It was a father, son and grandfather.
9. Four seconds (PelerinStJames) – two seconds for the first pair of strikes, then another 2 seconds between strike 2 and 3.
10. Every year. (David Tavener)
11. There are zero Ls in “that sentence” (St Marlowe).
12. It’s an operating theatre (DorsetSaint)
13. It was the Physics major (David Tavener, Clegthorpe). There was actually a typo in this question… it should have been -40 C/F, and they are the same… Ooops!
14. St M – almost, but not quite with “a trip to the store”. I was making a shopping list (David Tavener).
15. It was day time (St Marlowe, lilyg).
17. It’s white (DorsetSaint) – The only place you can go due south some distance, east (or west) any distance, and then back north the same distance and end up in the same place is if you started at the North Pole.
18. As above, it’s at the North Pole (DorsetSaint) – walking in a straight line from 3 miles south of the pole, and then any direction is south from the pole!
19. I’d pull the plug out (David Tavener).
20. The hens are in the tank (DorsetSaint) – female lobsters are called hens.
16. After my drive, I take a hunting holiday. For safety, I buy some rope. I look at one piece that is 100m long, but I have no idea how long it is (there are no labels on the spool). How can you tell the length of the rope?
Read the question carefully...That's all I'm saying!
I'm going fishing for a couple of days, so not sure of internet, but I'll be back by Wednesday!