Warning: file_put_contents(): Only 0 of 4990 bytes written, possibly out of free disk space in /home/www/wwwroot/zidian/69228.com/index.php on line 55 a毛片免费全部播放无风险,成人免费国产一区二区三区视频
1. N a modulus of elasticity, applicable to the stretching of a wire etc, equal to the ratio of the applied load per unit area of cross section to the increase in length per unit length 楊氏模量 ( symbol: )