Suppose the temperatures were 81°F, 84°F, 85°F, 86°F, and 85°F on Monday-Friday.
1. Does this describe a relation?
2. Describe the independent and dependent variables.
3. What are the domain and range?

answer:  

\boxed {\frac{1}{5}}  

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

solution-

60 *   \frac{1}{5}   = 12

90 * \frac{1}{5} = 18

75 * \frac{1}{5} = 15

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

hence, the answer would be \boxed {\frac{1}{5}}