I need help it for a dcp

Adepartment store purchases screen-printed t-shirts at a cost of $5 per shirt. they mark up the price 150% (making the selling price 250% of the store's purchase price) and put them on the sales floor. every month that a t-shirt doesn't sell, the store reduces the selling price by 25%.

If two parallel lines are cut by a transversal, interior angles on the same side of the transversal are supplementary. a. always b. sometimes c. never

Perform the indicated operation and write the answer in the form a + bi. (-5 + 2) + (3 - 6i)