Distinct name that match both subjects (math, science) from classname in level 2 only. Not sure where to even start. Any help is greatly appreciated!
name | subject | level |
bob | math | 2 |
hank | math | 1 |
joe | science | 2 |
bob | science | 2 |
joe | math | 2 |
ben | science | 2 |
carl | science | 1 |