•30. GWD-31-Q30
•The United States petroleum industry’s cost to meet environmental regulations is projected at ten percent of the price per barrel of refined petroleum by the end of the decade
A.The United States petroleum industry’s cost to meet environmental regulations is projected at ten percent of the price per barrel of refined petroleum by the end of the decade.
B.It is estimated that （by the end of the decade the cost to the United States petroleum industry of meeting environmental regulations） will be ten percent of the price per barrel of refined petroleum.
C.By the end of the decade, the United States petroleum industry’s cost of meeting environmental regulations is projected at ten percent of the price per barrel of refined petroleum.（It seems that the projection of cost is happening by the end of the decade）
D.重心失衡To meet environmental regulations, the cost to the United States petroleum industry is estimated at ten percent of the price per barrel of refined petroleum by the end of the decade.
E.The United States petroleum industry’s cost by the end of the decade to meet environmental regulations is estimated at ten percent of the price per barrel of refined petroleum.
fist of all, by the end of the decade indicates that we should use the future tense
second, cost as a noun has a standard usage : cost to something of doing sth
third, it is estimated that is used appropriately,
A不對因為by the end of the decade會誤修is projected
A、C、E中industry’s cost 用法错误，D中the cost 做主语和To meet……不一致，所以选B