# A Car & 20 Questions - Part II

- Author:
- Judah L Schwartz

Each of the intensive quantities formed in the applet “A Car & 20 questions” is of the form A/B where A and B are each measures of one of the following:
Distance in miles
Volume in gallons
Time in hours
Weight in pounds
Cost in dollars
The quantity A/B [for example, distance per weight in miles/lb, or time per volume in hrs/gal, etc.] can be thought of as a constant function of B [for example A/B = 30 mi/hr as a constant function of the time variable in hrs],
Alternatively, the quantity A can be thought of as a linear function of B [for example, A (miles) = 30 x B (hours)].
The left panel depicts A as a linear function of B. The right panel depicts A/B as a constant function of B.
Each of the 20 intensive quantities in “A Car & 20 Questions” can thus be represented graphically as a function in two ways.
Use the GOLD dot to adjust the number of A/B units
Use the BLUE dot to adjust the number of A units
Use the WHITE dot to adjust the number of B units