岩石()是选择爆破参数的重要依据。
A.可穿性
B.可爆性
C.耐压性
D.破碎性
参考答案:B
—My shirt is torn.
—______me a needle and thread, and I’ll fix it for you.
A.If you bring
B.If you had brought
C.Bringing
D.Bring
什么叫有效积温法则?有农业生产上有什么作用?