Hi, I'd like to kwon wether the following sentences are acceptable

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Thanks. Rip
1) How many times do yoy go swimming? I go swimming once a week
2) How often do you go swimmig?I go swimming once a week
3) When do you go swimming? I go swimming once a week
4) When do you go to swim? I go swimming once a week
5) How often do you go to the swimming pool? I go swimming once a week
I'm sure question 3 is correct. What about the other questions. Are they anyway acceptable? If not, why?
And....
6) What time does the film start? or
7) AT what time does the film start?
What about the answer to this question?
How much is the discount for children?
8) The discount for children is 10 pounds or
9) The discount for children is OF 10 pounds.
What about the answer to this question?
How much do tickets cost for adults?
10) They cost 10 ponds OR 15 pounds (it depends on where your seat is)
11) They cost 10 pounds AND 15 pounds (it depends on where your seat is)
12 They ARE 10 pounds (Can I use the verb to be like in the question How much are they? as an alternative to How much do they cost?)
13) That's 10 pounds