A:a; the
B:the; a
C:/; the
D:a; /
–I like the weather in Kunming. It's warm all year long.—Yes. And the temperature stays zero all the time.
“蛟龙号”是我国首台自主研制的作业型深海载人潜水器,如图所示,它是目前世界上下游能力最强的潜水器.假设某次海事活动中,“蛟龙号”完成海底任务后竖直上浮,从上浮速度为v时开始计时,此后“蛟龙号”匀减速上浮,经过时间t上浮到海面,速度恰好减为零,则”蛟龙号”在t0(t0<t)时刻距离海平面的深度为( )
①燃煤发电 ②地热发电 ③水力发电 ④风力发电