Is the nor gate a universal gate what does an invert bubble

Question

Greetings, I need assitance on Logic Diagram.

1. Is the NOR gate a universal gate?
2. What does an invert bubble at the input of a logic gate mean? (Hint: Active High or Low)
3. Consider the following statement "A car alarm will sound if the door is open or the window is open"

Translate that statement into a logic diagram. Use 'A' as the input from the car door and 'B' as the input from the car window.

Can you think of other statements that can be translated to logic circuits?

1. Discuss the statement "Translating logical statements into logic circuits."