Light is composed of protons, which have no mass, therefore light has no mass and cant weigh any thing.
A shadow is bigger than you but doesn't weigh anything.
NO.
No.
Altitude doesn't weigh anything.
yes
Well they can weigh anything but the average is about 7 pounds
the galexy does not weigh anything its mass is around 1,153,678000000000000000000000000000000000000 kg
an ocean
your shadow
This will depend on what type of goose. You cannot weigh anything online.
5 18 is a number which is an abstract concept. It does not weigh anything!
A shadow or an reflection is as big as a human, yet it doesn't weigh anything.