Final answer:
The magnitude of the difference between a windchill factor of -43 and a windchill factor of -66 is 23.
Step-by-step explanation:
The magnitude of the difference between a windchill factor of -43 and a windchill factor of -66 can be calculated by subtracting the two values.
Thus, the magnitude of the difference between -43 and -66 is |-43 - (-66)| = |-43 + 66| = 23.
Therefore, the magnitude of the difference between a windchill factor of -43 and a windchill factor of -66 is 23.