Answer:
Explanation:
The negative only matters reallly if you are dealing with a 2d system. I could even define down as positive and up as negative. However, usually you are taught that down is negative. It really doesn't matter because a force is a force. It is only given a direction relative to another force or vector direction.
Answer:
The plants depend on animals and animals depend on plants.
Plants depend on animals for nutrients, pollination and seed dispersal. Animals are totally dependent on plants. First of all plants produce oxygen which is vital for life on earth. Then, for many animals plants are their basic food, or if plants don’t make up 100 % of their diet, plants are nevertheless essential in their food supply.
The common method would be to use Balance, If you think about it, on other planets, the balance weights change by the same factor as the object you are measuring. Your mass measured with a balance would be the same on the moon as it is on Earth. Weight is a measuring of gravity's effect on something. Mass is another story, it's the amount of matter in an object. Move to another planet and its object's weight will change, however, its mass will remain the same.
