1a) 2 properties that glass and plastic always share
1b) 2 properties that glass and plastic sometimes share
2) what advantages do bottles made from plastic have?
3) what disadvantages are there when you use plastic bottles?
4) why are plastic bowls not used for heating on a cooker?
5) what are the disadvantages of using metal for a toy for a baby?
6) why is plastic often used for children's toys?
7) what properties would you look for in materials to make a kite?

Mass is the amount of matter in an object.  weight is the measurement of the pull of gravity on an object.  say for example, you travel to the moon which has a different gravitational field compared to the gravitational field of earth. (gravitational fields: earth = 1, moon = 0.165)  now when you are on the moon, the pull of gravity on you is different than on the earth. and as weight is the measurement of the pull of gravity on an object, that means yes, your weight can and will change on the moon.  however, on the moon, on earth or even on jupiter, the amount of mass inside of you remains the same. meaning your physical mass remains constant.  in conclusion it is possible for your weight to change as your mass remains constant.