Final answer:
The temperature 5°C below zero is represented by the integer -5, and temperature is considered a scalar quantity because it has magnitude but no direction.
Step-by-step explanation:
The temperature 5°C below zero is represented by the integer -5. This is because the negative sign is used to denote temperatures that are below the freezing point of water (0°C). In this context, a positive integer would indicate a temperature above zero. Therefore, the correct answer is c) -5.
Regarding the temperature prediction in a weather forecast, temperature is considered a scalar quantity because it only has magnitude and no direction associated with it. Scalar quantities, like temperature, describe how hot or cold something is but do not provide information about the direction of the heat transfer which is why they are not vectors.