15.某班同学在探究弹簧的长度与外力的变化关系时,实验得到相应数据如下表:则y与x的函数图象是( )
0 308994 309002 309008 309012 309018 309020 309024 309030 309032 309038 309044 309048 309050 309054 309060 309062 309068 309072 309074 309078 309080 309084 309086 309088 309089 309090 309092 309093 309094 309096 309098 309102 309104 309108 309110 309114 309120 309122 309128 309132 309134 309138 309144 309150 309152 309158 309162 309164 309170 309174 309180 309188 366461
| 砝码的质量x(克) | 0 | 50 | 100 | 150 | 200 | 250 | 300 | 400 | 500 | 600 |
| 弹簧的长度y(厘米) | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 7.5 | 7.5 | 7.5 |
| A. | B. | ||||
| C. | D. |