Question 655387
Ignore the 'b's in the middle since they don't form the outer perimeter. 


All you need to do is add up the six "b+1" terms that are the lengths of the six outer sides to get


P = s1 + s2 + s3 + s4 + s5 + s6


P = (b+1)+(b+1)+(b+1)+(b+1)+(b+1)+(b+1)


P = b+1+b+1+b+1+b+1+b+1+b+1


P = (b+b+b+b+b+b) + (1+1+1+1+1+1)


P = (6b) + (6)


P = 6b + 6


So the answer is choice C