This seems to be an engineering sample CPU. Since these are pre-production, that could mean it’s basically a fully functional CPU. It could also have serious issues.

It doesn’t ask you to subtract the numbers, but to calculate the distance (i.e. the absolute value of the subtraction). So depending on which numbers are paired up, the sign of the pair can be different.

Sure, the skull is biodegradable. But didn’t you know that large-scale human farming is responsible for the vast majority of CO2 emissions?!