Решите задачки срочно ! Алканы и их свойсва!!!!

1.  Обьем кислорода необходимый для горения пропана обьемом 40л(н.у.)? 

2.спалили бутан обьемом 44,8 л.Обьем воздуха(20% кислорода)использованого на его горение ?

помогите пожалуйста((1. She scarcely realized what (happen). 2. Oh, Jane! I didn't think you (be) so unkind. 3. Mary (to return) to the room. Al (to sit) beside the gas fire and (to take off) his shoes. 4. Her eyes (to be) puffed, and she obviously (to cry) that afternoon. 5. She realized that he (try) to tell her how lonely he (be). 6. His cheek (to be) cut. When she (to see) it she (to say): "Oh, you (to fight) again". 7. I thought I (sleep) well, being tired. 8. She (to make) me promise to say nothing about it till she (to have) a chance of breaking the news to her father gradually. 9. She asked if Mr Clennam (tell) her where he (live). 10. As we (to drive), her eyes (to stare) rigidly out of the car window. 11. Sir Wilfred knew, from the frequency with which she used her handkerchief, that tears (run) down her cheeks. 12. Delany (to sit) up in bed and (to eat) his dinner when Jack (to come) into the room. His complexion (to be) ruddy. Obviously he (to be) shaved. He (to have) a glass of red wine with his meal. He (to wave) his fork as he (to see) Jack. 13. He (to remain) in his seat, as though studying his programme, till the three (to pass) out into the foyer. 14. Darkness (to fall) when he finally (to return) to the hotel. He (to say) nothing to Pat except that he (to turn) down the job. He (cannot) give her any explanation until he completely (to understand) the meaning of what (to happen). 15. I (to sit) there for about ten minutes, pretending to read, when someone (to sit) down at my table. 16. She (to look) up at him from where she (to sit). Her make up things (to lie) in front of her. She (to do) her face. 17. While his wife (to read) the letter, he (to cross) to the window. 18. As Hugh and I (to come) down the steps we nearly (to ran) into my father.