某地位于140°W,与它组成经线圈的经线是( )
A:40°E
B:140°E
C:60°E
D:40°W
从楼顶由静止开始下落的物体落地用时为2.0s,若要让物体在1.0s末落地,应该从哪儿开始自由下落(取g=10m/s2)( )
— Dirty water shouldn't be poured into rivers.
— _______. It will cause pollution.
“绿色发展”、“低碳生活”等理念逐渐深入民心,下列做法不符合这一理念的是( )
—I'm sorry to hear that. You ______ be very sad.