Discuss whether the values are the same or different. If they are different, provide the reasoning and explain how to reduce this difference between calculated and measured values. Explain what happens when the transistor changes to a PNP transistor. How does the change in the transistor effect the current and voltage in the circuit?

The illuminance of a surface varies inversely with the square of its distance from the light source. if the illuminance of a surface is 120 lumens per square meter when its distance from a certain light source is 6 meters, by how many meters should the distance of the surface from the source be increased to reduce its illuminance to 30 lumens per square meter?