stat problem

You are playing darts on a circular target of radius 30cm. If you hit within 10cm radius from the center. you get 10 points. If you hit further than 10cm but less than 20cm radius from the center you get 5 points. If you hit further than 20cm, you get 1 point. Suppose you closed your eyes and throw one dart that hits the target at some random point. 1. What is the probability that you got 10 points? 2. What is the probability that you got exactly 5 points? 3. What is the probability that you got at least 5 points