For the following examples, tell whether there is positive association, negative association, or no association.

1. The number of inches of rain per hour and the height of water in a reservoir.

   Hint (a):

   As the amount of rain fall increases, the height of water in a reservoir increases.

   Answer (a):

   Positive association.

2. The amount of food a person eats and how many pets they have.

   Answer (b):

   No association.

3. The height of a tree and the amount of nutrients it gets.

   Hint (c):

   The more nutrients a tree gets, the more it will grow.

4. The number of hours spent hiking in the mountains and the amount of water left in your water bottle.

   Hint (d):

   The longer you hike, the less water you will have in your bottle.