A:水田为主
B:作物有水稻、油菜、棉花等
C:一年两熟至三熟
D:西部降水较少,适宜发展畜牧业
A:Our new school is big and nice. There is a gym in our school now.
B:Yes, and there is a big library, too.
(1)画出图甲中出射光线对应的入射光线.
(2)画出图乙中细线对木块A拉力的示意图.
(3)小磁针静止在磁体旁,如图丙所示,标出小磁针的N极;
(4)如图丁所示,用螺丝刀撬钉子,O为支点,画出动力F的力臂L.
已知抛物线C:y2=2px(p>0)的焦点为F,直线y=4与y轴的交点为P,与抛物线C的交点为Q,且|QF|=2|PQ|,过F的直线l与抛物线C相交于A,B两点.