Answer:
here you go
Explanation:
Why do your lights actually come on almost instantaneously? ... Wiring the house in parallel does not make a difference – there is no current flowing through the light bulb when the switch is off no matter how the house is wired. If there were a current already, the light would be on!
Answer:

Explanation:
Let the speed of light in vacuum is c and the speed of light in medium is v. Let the angle of incidence is i.
By using the definition of refractive index
refractive index of the medium is given by
n = speed of light in vacuum / speed of light in medium
n = c / v ..... (1)
Use Snell's law
n = Sin i / Sin r
Where, r be the angle of refraction
From equation (1)
c / v = Sin i / Sin r
Sin r = v Sin i / c

As the light pass through different media, it experiences a refraction. This is a phenomenon where the speed and direction of light changes. If the ray of light moves towards the normal line, the angle is decreased. So, is the speed of that light.
The correct answer is I disagree. Elements form all pure substances, but some pure substances include elements bonded together to form molecules and compounds.
Elements are pure substances but these elements also make other things such as water. The water molecule is made of two elements called oxygen and Hydrogen. Now water itself is a pure substance as it is chemically bonded hydrogen and Oxygen but it is composed of more than one element