_____ in the book he was reading on the way, the boy was almoat knocked down by a car.

A Having absorbed    B being absorbed      C Absorbed      D to be absorbed

一重为20N的薄铁皮水桶装满重力为98N的水，用手提桶并将桶浸没到大水缸中（未与缸底接触），此时手对桶的拉力为 ______N．