Samantha is making cookies. She uses 2 1/2 cups of flour for each batch and plans to make 4 batches. How many total cups of flour will she need? If she decides to make an extra 2 batches, how many cups of flour will she need in total?

A scuba diver is exploring underwater. She descends to a depth of −35 feet and then swims up 15 feet. Represent this scenario as an expression involving absolute values and calculate how far below the surface she is now.