If the same two elements were detected in a distant star that was moving away from earth , how would the spectral lines appear?

An object moves from the position +34m to the position -15m in 15 seconds. what is it's total displacement? what is it's average velocity?

Identify the theory that can be used to explain each phenomenon. answers diffraction: wave theory interference: wave theory reflection: both particle and wave theories refraction: both particle and wave theories

Why is rain likely when warm, moisture-laden air meets cold air? a) the lighter warm air will rise and cool down, causing condensation and rain. b) the cold air moves faster and pushes the warm air away, causing condensation and rain. c) the moisture in the warm air condenses on contact with the cold air, causing rain to fall. d) the cold air mixes with the warm air, reducing its temperature causing moisture to condense.