Cheryl has a mug that she says is made up of matter. heather says that the hot chocolate inside the cup is made up of matter, too. keaton says that the steam coming from the cup is also made up of matter. mikayla says that none of it is matter because matter is too small to see. which best describes who is correct?

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?