| | | | | | | ⒈ | | 3 4 | 4 6 40 60 | | ⑴ | | | | ⑵ | | | | | 20cm | | 3 10cm 6 | | | | 15 24cm | 1 1.5cm | | | | 5 7 | ⑶ | 2 4 5 | 15 20cm | | | | | 10 | | 667 10 15 | 5 7 | | ⑷ | | | 30 | | ⒉ | 4 7 | | | ⑴ | | | 2 | ⑵ | | | | | | | | | ⑶ | 2 3 | 4 5 | 1 2 | | 667 | 15 — 20 | | ⑷ | | | | |