The main purpose of the Customs supervision and control is to ______ China, seconomic, trade, scientific, technological and cultural exchanges with other countries.

A．supervise
B．control
C．promote
D．limit

FBE粉末在某一温度下固化95%、98%、99%、99.5%时固化分别为1.8min、2.5min、3.2min、4.0min，胶化时间为18s，胶化段为350mm，3PE最大涂敷速度涂敷速度为（）。