已知某时刻某地700hPa的纬向风、经向风和比湿分别为4.0m/s、-3.0m/s和1.0g/kg，若重力加速度取10<img src="https://static.zxtiku.com/wangke/imgs/topic/3b7984fbfd6138d73a29e80ef55f341d.jpg"/>，则该时刻该地700hPa水汽输送的大小约为（）<br/> A、<img src="https://static.zxtiku.com/wangke/imgs/topic/ce2332dc219ffe9f20dcef2f7a966b32.jpg"/><br/> B、<img src="https://static.zxtiku.com/wangke/imgs/topic/421b0ec6858cab51fb2cbe8358a90c85.jpg"/><br/> C、<img src="https://static.zxtiku.com/wangke/imgs/topic/18ae5f009fde35d3c2697ffc1b2819dc.jpg"/><br/> D、<img src="https://static.zxtiku.com/wangke/imgs/topic/f8d83b69088e524e622601a99af24bb0.jpg"/>