A Data Set Contains the Observations 8, 1, 6, 7 $\left( \sum { x } \right) ^ { 2 }$

A data set contains the observations 8, 1, 6, 7, 2. Find $\left( \sum { x } \right) ^ { 2 }$

A) 576
B) 154
C) 48
D) 24