According to the Chemical Data Guide，which reactive group(s) is/are not compatible with the products polybutene and o-xylene? （）

What action must be taken when an individual cargo tank is closed off from the inert gas system by the tank isolation valve?（）

The fresh air intake of the inert gas system（）.

Releasing oil from the sea anchor of a survival craft may（）.

Using an inert gas system on a tanker has which advantage(s)? （）

Petroleum cargo tanks should not be topped off at deck level when loading on a cold day because（）.

Regulations require that tank vessels handling grade B liquids shall have their cargo pumps separated from all sources of vapor ignition by（）.

Regulations require that cargo pumps in tankers carrying grade D liquid cargo shall be isolatedfrom sources of vapor ignition by（）.

The purpose of the deck seal in an inert gas system is to prevent（）.

The designations A，B，C，D and E grades of cargo refer to the（）.