Answer:
if i were you i would try to do the work because if you let someone else you wont be able to understand the question
Speed v = distance travelled / time taken
v = d / t
v = 540 / 60h
v = 9 km /h
Not totally sure but i would say a normal? its not refraction or incidence if its perpendicular and i dont think its a mirror if its an imaginary line so yeah normal (normals are always perpendicular to their surface too i think so)
Answer:
Dark matter does not affect our view, humans can see through them.
Explanation:
They do not affect our view because we can see right through the (weakly interacting) dark matter, as they do not interact or interfere with electromagnetic force.
Dark matter are often invisible substances and are difficult to spot because they don't absorb or reflect light.
An ice cube causes hot coffee to become cool because the amount of coldness contrasts the hot coffee to make it a little cooler
