一个静定的平面物体系它由六个单个物体组合而成，则该物体系能列出（）个独立平衡方程。
A、3
B、6
C、9
D、12
参考答案：A
6个月以内婴儿无热性支气管肺炎应考虑
A．葡萄球菌肺炎
B．合胞病毒肺炎
C．革兰阴性杆菌肺炎
D．肺炎支原体肺炎
E．衣原体肺炎
______ that he has no qualifications in business management, Ken plans to gain the necessary skills by taking a part-time course.
A．Concerning
B．Concerned
C．Being concerned
D．To concern
