Use Polya's four-step problem-solving strategy to solve the following problem. Suppose 36 student signed up for classes during an orientation session. If exactly 22 of them signed up for chemistry and...

Use Polya's four-step problem-solving strategy to solve the following problem. Suppose 36 student signed up for classes during an orientation session. If exactly 22 of them signed up for chemistry and exactly 18 of them signed up for English, how many of them signed up for both chemistry and English? How many of them signed up for chemistry only? How many of them signed up for English only?