Question

1. why do the stars in a constellation not seem to change position over time?

Explanation:

The stars in a constellation are extremely far from Earth. Their actual movements (proper motion) are so small over human timescales that they appear fixed. Also, the distance makes their relative positions from Earth's perspective seem unchanged as we observe them, even though they move in space.

Answer:

The stars in a constellation are very far from Earth. Their actual motions (proper motion) are negligible over human - observable time periods, and from Earth's perspective, their relative positions appear unchanged.