A thermostat registers temperature error as E = |T - 20| where T is the temperature in °C. If the error is 5°C, what possible temperatures T satisfy this?

• A. T = 25°C or T = 15°C
• B. Every temperature between 15°C and 25°C inclusive.
• C. T = 5°C or T = 35°C
• D. Only T = 25°C because temperature cannot be less than 20°C in this setup.

Answer: (A)