Paper produced every year is           the world’s production of vehicles

A three times weight of                   B three times the weight of

C as three times as heavy                    D three times so heavy as

在以下变更事项中，属于工程变更的是()。P227

A.设计变更

B.进度计划变更

C.施工条件变更

D.付款方式变更

E.施工顺序变更