No, permutation is for finding out orders like how many ways can you arange the letters x,y,z the answer is 6, because xyz, xzy, yxz, yzx, zyx, zxy
permutations are a branch of probability
probability is (desired outcomes)/(total possible outcomes) or
10/total people registered
Add positive 28 to get the sum 0
Since ∠2=60° = ∠8 so it will also be 60 °
the sum of the both are 60°+∠7=180°
∠7= 180°- 60° = 120°