| | | | | | | 1. | | | | | | | 2. | | | 21 35 | | | 35 56 2 | | | | | | | 3. ︵1︶ | | | | | | | | | ︵2︶ | | | | | | | | 4. | | | 3 5 | | | | | | | | | | | | | | | | | ︵︽ | ︾ | |