Each light switch in the classroom allows you to turn on one row of lights. what conclusion can you make about how the rows of lights are connected and justify this answer. a) the rows must be hooked up in parallel or only one row could be turned on at a time. b) the rows must be hooked up in series or all the rows of lights would either turn on or off. c) the rows must be hooked up in parallel or all the rows of lights would either turn on or off. d) the rows must be hooked up in parallel or all the rows of lights could only be controlled by a single switch.

C ) The rows must be hooked up parallel or all the rows of light would either turn on or off.

Explanation:

1. Because if the rows would be in series then turning on one/off row means turning on/off all the rows respectively. So option B is totally incorrect.

2. If they are in series its obvious that all the rows would either on or off. So option "A" is incorrect because of its argument.

3. Again if they are in series it doesn't mean that they could only be controlled by one switch thats why option "D" is incorrect.

So only option C is correct with logical argument.

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.