In a race, there are four competitors: Alex, Brian, Charlie, and Derek. Alex finished before Brian but after Charlie. Derek finished last. Who finished first?
In a class, there are three types of students: A, B, and C. Type A students are good at mathematics, Type B students are good at science, and Type C students are good at literature. If a student is good at science, which type do they belong to?
In a family, there are three siblings: Tom, Jerry, and Anna. Tom is older than Jerry but younger than Anna. If Anna is 10 years old, how old is Jerry at most?