保单的承包范围有哪些？什么是general average？
LEVELS OF COVER
Level A
This level covers loss due to:
1) problems with the carrying vessel or train, such as collision, explosion, fire, sinking, capsizing, running aground, washing overboard, loss on loading or unloading and derailment;（运输船或火车的问题，如碰撞、爆炸、火灾、下沉、倾覆、搁浅、冲舷外、装卸失物和脱轨）
2) events such as lightning, volcanic activity and earthquakes;（闪电、火山活动和地震等事件）
3) theft and non‑delivery.（盗窃和未交付）
Level B
This level includes all of the risks in 1) and 2).
Level C
This level includes risks listed under 1) only.
The insured is not covered for:
1.misconduct of the insured;（被保险人的不当行为）
2.poor packing;（包装不良）
3.any inherent vice of the cargo, such as a tendency to deteriorate over time;（货物的任何固有缺陷，例如随着时间的推移而恶化的趋势）
4.insolvency of the carrier;（承运人的破产）
5.an unseaworthy vessel.（不适合航行的船只）
Level A insurance also protects against ‘general average’ For example, if it were necessary to jettison some cargo to save a ship, the normal rule is that all those with goods on board share the loss, even if their own cargo is not thrown overboard. But the general average clause protects the insured against this loss. The insured would also be covered in the event of a dispute as to which ship was to blame for a collision. （例如，如果有必要抛弃一些货物来拯救一艘船，正常的规则是所有在船上有货物的人分担损失，即使他们自己的货物没有被扔出船外。但共同海损条款保护被保险人免受这种损失。如果发生关于哪艘船应归咎于碰撞的争议，被保险人也将获得保障。）
来自CITF2021， 6.8.1 Types of insurance
