Your cafeteria is serving chicken noodle soup today, which it sources from a distributor and then warms up locally in the kitchen. The soup now sits in a large bowl and a server uses a large ladle to fill the soup into the smaller bowls handed out to the students. Consider the following variables:
1. Outside temperature.
2. Duration that the soup was heated before being put in the bowl.
3. Temperature of the soup in a student's bowl.
4. Temperature level to which the soup is warmed up.
5. Insulation of the bowl used for storing the soup.
6. Duration that the soup bowl is open when the server inserts the ladle to serve a student.
Which of these variables are (a) input variables, (b) output variables, and (c) environmental variables.?

The correct answers to the question are

1. Environmental variable c,

2. Input variable a,

3. Output variable b,

4. Input variable a,

5. Input variable a,

6. Input variable a

Explanation:

1. Outside temperature.  

This is is an environmental variable regarding where the observation is taking place

2. Duration that the soup was heated before being put in the bowl.

This can be controlled so it is an input variable

3. Temperature of the soup in a student's bowl.

This depends on the initial temperature the soup was heated to so it is an output variable

4. Temperature level to which the soup is warmed up.

Input variable as it can be controlled o varied

5. Insulation of the bowl used for storing the soup.

This is an input variable as the type of bowl can be selected

6. Duration that the soup bowl is open when the server inserts the ladle to serve a student.

server or the operator of the cafeteria

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