⑴____A. always B. often C. fruit
⑵____A. vegetable B. first C.fruit
⑶____A. eight B.three C.first
⑷____A. his B. your C.I
⑸____A. drink B.sport C. eat
△ABC内接于以O为圆心,1为半径的圆,且OA→+2OB→-OC→=0→,则OC→·AB→的值为( )
—Er,it's about ten minutes'walk.