осуществить превращения al-al2o3- al(oh)3-al2(so4)3

The Bedes liked the house which they (buy)1 three weeks before. It (stand)2 on the hill and (be)3 in perfect condition."Now I (feel)4 quite happy," Gwen (say)5. "We (live)6 in the house for 3 weeks and I (get)7 more and more proud of it. I (think)8 I (can)9 live in the house all my future life." James (like)10 their new house very much too. He often (sit)11 in the old armchair (look)12 into the fire. These (be)13 the happiest minutes in his life. He (watch)14 the logs (burn)15 in the fire and (think)16 he (be able to)17 (sit)18 like that for a long time.
The Bedes (be)19 in the house for twenty-two days when their first post (arrive)20. The postman (bring)21 three large envelopes. There (be)22 a letter from Gwen's sister. Gwen (hope)23 she (read)24 it after the postman (go)25 away, there (be)26 business papers for James in the second envelope, the third envelope (address)27 to "Mrs Alison Ray". Gwen (want)28 (give)29 that letter to the postman, but the latter (say)30 that as the address (write)31 correctly somebody (may)32 (call)33 on them later. He (ask)34 the Bedes (keep)35 the letter for some days. He (promise)36 (return)37 at the end of the week and (say)38 he (take)39 the letter to the post-office if nobody (ask)40 for it.
Gwen (leave)41 the letter on the hall table but the following morning it (disappear)42. Gwen (decide)43 that James (hide)44 it and asked if he (not touch)45 the letter. "Who (take)46 the letter then? What we (tell)47 the postman when he (come)48? What all this (mean)49?" (worry)50 Gwen.

На автомашине с прицепом нужно перевезти 1080 ц угля. За один рейс на машине увозили 30 ц, а на прицепе - в 2 раза меньше. Сколько рейсов надо сделать, чтобы перевезти весь уголь?