Ex9 4

$\def\abs#1{|#1|}\def\i{\mathbf {i}}\def\ket#1{|{#1}\rangle}\def\bra#1{\langle{#1}|}\def\braket#1#2{\langle{#1}|{#2}\rangle}\def\tr{\mathord{\mbox{tr}}}\mathbf{Exercise\ 9.4}$

a) How many iterations should Grover's algorithm use in order to find one item among sixteen?

b) If we apply one fewer than the optimal number of iterations and then measure, how does the success probability compare to the optimal case?

c) If we apply one more than the optimal number of iterations and then measure, how does the success probability compare to the optimal case?