(57600÷900+64×99)÷25.
(57600÷900+64×99)÷25
=(64+64×99)÷25
=64×(1+99)÷25
=64×100÷25
=256.
He _____ a million yuan to Wenchuan since the earthquake.
[ ]
A. has given away
B. gave away
C. have given away
D. gives away
如图所示,O为杠杆的支点,在B处挂一个小球,AO=OB=BC,为使杠杆在水平位置平衡,画出施加在杠杆上最小动力F1的力臂l1,并标出F1的方向。