1) Find the illumination 4.2 m below a 415 lm lamp. 2) A screen is placed between two lamps so that they illuminate the screen equally. The first lamp emits a luminous flux of 1445 lm and is 2.7 m from the screen. What is the distance of the second lamp from the screen if the luminous flux is 2350 lm? 3) Two lamps illuminate a screen equally. The first lamp has an intensity of 101 cd and is 4 m from the screen. The second lamp is 5 m from the screen. What is the intensity of the second lamp? ---------------- These should be very easy. However, I'm doing this for a friend and I don't have his book or any of the formulas. Help me out?