In this diagram, heat energy is being added over time. The vertical axis shows an increase in temperature, and the horizontal axis shows the passage of time. What is happening to the temperature at Point B? A. The temperature is not rising because the molecules are slowing down. B. The temperature is not rising because the heat is being used to break the connections between the molecules. C. The temperature is dropping as the molecules break apart from each other. D. The temperature is rising as the molecules break apart from each other.

prolly a beacuse the momentuem the car has increases while going down hill

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.