13．下表是一位病人的体温变化记录统计表．根据相关数据制成合适的统计图．
| 时间（时） | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 |
| 体温 | 39.5 | 38 | 39 | 39.2 | 38 | 37.5 | 37 | 36.8 | 37 | 37.2 | 37.1 |
7．解方程．
0 129450 129458 129464 129468 129474 129476 129480 129486 129488 129494 129500 129504 129506 129510 129516 129518 129524 129528 129530 129534 129536 129540 129542 129544 129545 129546 129548 129549 129550 129552 129554 129558 129560 129564 129566 129570 129576 129578 129584 129588 129590 129594 129600 129606 129608 129614 129618 129620 129626 129630 129636 129644 199269
| 2+1.8-5x=3.6 | 2x÷2.3=4.5 | 31.7-x=20.9 |
| （100-2x）÷5=4 | 6x+4x-11=2.9 | 7（x-1.2）=2.1． |