Five friends were looking at their shadows early one morning. They wondered what their shadows would look like by the end of the day. This is what they said: Jamal: “My shadow will keep getting longer throughout the day.” Morrie: “My shadow will keep getting shorter throughout the day.” Amy: “My shadow will keep getting longer until it reaches its longest point and then it will start getting shorter.” Fabian: “My shadow will keep getting shorter until noon and then it will start getting longer.” Penelope: “My shadow will stay about the same from morning to day’s end. Which friend do you most agree with? Describe your thinking. Explain the reason for your answer.

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. 

The answer is nitrogen-containing bases