沸点、闪点、自燃点之间的关系是什么？
参考答案：
油品沸点愈低，则闪点愈低，自燃点愈高；沸点愈高，则闪点愈高、自燃点愈低。
Silver is the best conductor of electricity, copper it closely.
A．followed
B．to follow
C．following
D．being followed
曲线y2=4x关于直线x=2对称的曲线方程是[ ]
A、y2=8-4x
B、y2=4x-8
C、y2=16-4x
D、y2=4x-16
