They are going to Dalian _________ a school trip in the summer holiday.
A:for
B:to
C:at
D:with
甲乙两个物体相距20米同时同向运动,乙在前方,甲做匀减速直线运动,乙做匀加速直线运动,如图所示,则( )
吃冰棒和皮肤上擦酒精都感到凉快,从物态变化角度看,前者主要是利用冰棒 ____,后者是酒精 ____