To develop more accurate population forecasts, demographers have to know a great deal more than now about the social and economic determinants of fertility.
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- have to know a great deal more than now about the social and economic
- have to know a great deal more than they do now about the social and economical
- would have to know a great deal more than they do now about the social and economical
- would have to know a great deal more than they do now about the social and economic
- would have to know a great deal more than now about the social and economical
The KEY is E, why yah? :-( My answer is B. |