Jack leaves his house and walks north for 30m. he turns left and walks west for 30m. he then turns left again and walks another 30m. what is the point of reference for jack’s motion?

Jack's house

Explanation:

Point of reference is a point in a space that can be used to tell where other things are positioned. It is also known as the reference point. A simple way to put this is the starting point. As you can see in your example, Jack started from his home and is moving in directions depending on his house's location.

b, acidosis

acidosis is when the human body attempts to return the bloods ph levels back to normal when the blood is acidic

"a.) well–developed vascular system."