d1+d2+d3....d11=2*e where di= degree of vertex i
Let minimum degree be d'. Then d'<=di for all i.
Replacing all the degrees with d' we get,
d'+d"......+d'(11 times each for 1 of the 11 vertices) <= 2*e
11d'<=2*e
d'<= 2*e/11
e=16 so d'<=2.9 hence d'=2.