Logical Deduction - General Questions

All A are B. No B are C. Which statement must be true?

If a number is divisible by 6, it is divisible by 3. 45 is divisible by 3. Which is correct?

All software engineers in the company know Git. Divya does not know Git. Which conclusion follows?

No reptiles have fur. All snakes are reptiles. Which conclusion follows?

If the alarm rings, everyone leaves the building. Everyone left the building. Which is correct?