PLEASE HELP thank you:) Carlos is investigating the brightness of a lightbulb.
The brightness of a lightbulb, B lumens/m2, is inversely proportional to the square of the
distance from the lightbulb to the point where the brightness is being measured, Dm.
At 3 m from a lightbulb, Carlos measures the brightness of the lightbulb is 4.5 Lumens/m2
(a) Work out the brightness of the lightbulb at 5 m away.
Give your answer in lumens/m2

At an unknown distance from the lightbulb, Carlos measures the brightness of the lightbulb
to be 0.5 lumens/m2
(b) Work out the distance from the lightbulb where the brightness is 0.5 lumens/m2