Answer:
If the museum engages in price discrimination and decides to take both "contracts" (adults and students), the profit the museum will earn is $800.
And it goes like this:
Adults: 100 x $12 = 1.200
Students: 200 x $8 = 1.600
Income: 1.200 + 1.600 = 2.800 total incomes if both contracts happens in the same day.
Profit: 2.800 (Income) - 2.000 (costs) = 800 profit