The cost of the first purchase was $612.
The cost of the 2nd purchase is c.
Her credit limit is $2000.
The total amount she spent will be
[tex]612+c[/tex]Since the cost is above the credit limit, it means that the total cost is greater than 2000.'
Therefore, we can write the expression mathematically as
[tex]612+c>2000[/tex]Therefore, the correct option is OPTION D.