21. light changes its direction when travelling through a new medium because denser mediums have a higher angle of refraction.
Answer: Matter is how much space or opacity an object takes up. In short anything that take up space. Things like balls, trees, and even people are all made of matter. Mass is how much matter a object has. Air also has mass also, even though we can't see it. Things like cars, buildings, even planets have mass.
Explanation: Paragraphs are sometimes 4-6 sentences.
C and d have the same amount of protons and electrons
Answer:
30 degrees
Explanation:
Reflects off of mirror 1 at 60 degrees....this makes it incident to second mirror at 30 degrees ....then angle of reflection equals this angle of incidence = 30 degrees
See atached diagram
