(See cheat sheet for summations. E.g. 1+2+3++(n1)+n=t=1t, has closed form: 2n(n+1). ) a) (5 points) Assume that void mistery (int X ) ; has time complexity O(X) Fill in the time complexity of the function call: mistery ( 8); TCmistery(8)=O() b) (10 points) for (k=1;k=0;k=k1) for (t=0;t