Reflection of light is a fundamental property of all mirrors. bill and bett wanted to produce a virtual image using one of the mirrors supplied by their teacher. to do this, they should choose a mirror.

In a plane mirror the image formed is virtual because it is a copy of the real object. It looks as if the object is behind the mirror and not in front of it or on the surface, but it is not really there. However, it can be seen when we focus it with our eyes.  

In addition, the image is symmetrical, because apparently it is at the same distance from the mirror; of  the same size as the object and upright, because it retains the same orientation as the object.

power out to power in less than 100%

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg