蔗糖溶液中溶质是____ ,碘酒中溶剂是____.
—Take the blue one, as the colour looks good your skin.
若2x2+1与4x2-2x-5互为相反数,则x为( )
在测定金属丝的直径时,螺旋测微器的度数如图所示.可知该金属丝的直径d=____mm.