A lamp is a one-bit computer system with a very slow clock speed. You can use it to communicate. It has no memory.
An oven is not a computer system although the electronic timer in modern electric ovens is a computer.
Is this a homework question? Tell your teacher the question is too ambiguous. Neither a lamp, nor an oven is a computer system.
This is more of a semantics question than anything else. depending on how you define a "computer system" just about anything can be a computer system.
stupid question, but I need to know, thanks :)