Using either the district plan or the proportional plan to reform the Electoral College .

The question is incomplete and the full version can be found online.  

would not ensure that the winner of the popular vote would become President

Explanation:

Neither the district plan nor the proportional plan to reform the Electoral College would ensure that the winner of the popular vote would become President.

The district plan still allows the possibility of electing a President that wins the electoral vote but loses the popular vote.

And the proportional plan does allow the election of the President by popular vote but it doesn´t ensure that the winner of the popular vote would become President.

what is the tax base for the sales tax?

it should be (usually ) 6%

the answer would be c. sediment buildup on continental slope

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