#2 is the one i need help with!!

The price of a visit to the dentist is \$50$50. if the dentist fills any cavities, an additional charge of \$100$100 per cavity gets added to the bill. if the dentist finds nn cavities, what will the cost of the visit be?

Type the next three numbers in a sequence 80, 90, 85, 95, 90, 100, 95, 105

Awoman won a 4000-m race with a time of 12.089 min. what was her rate?