I don’t really see an outlier but if i have to choose one i would do the 678
Answer:

Step-by-step explanation:

Answer: 8
Step-by-step explanation: 12 minus 4 equals 8
Every positive number has two square roots - a positive and a negative (unless the value is 0).
The length of something can only be a positive number and since there is only one positive square root, there is only one answer.