题干
I don't like doing the dishes because it's ____ .
A：interesting
B：boring
C：interested
D：bored
答案(点此获取答案解析）
B
I don't like doing the dishes because it's ____ .
A：interesting
B：boring
C：interested
D：bored
的轻杆下端固定一个质量为
的小球，上端连在光滑水平轴上，轻杆可绕水平轴在竖直平面内运动（不计空气阻力）．当小球在最低点时给它一个水平初速度
，小球刚好能做完整的圆周运动．若小球在最低点的初速度从