Memory Access Miss Rate, can you explain why the answer for each of these multiple choice questions?

vii. Memory Accesses: 0, 4, 0, 4, (repeats). The Miss Rate is: (a) 0% (b) 25% (c) 40% (d) 50% (e) 100% (f) none of the above viii. Memory Accesses: 0,1, 2, 3, 5, 2, 3, 5, 3, 2 The Miss Rate is: (not repeatable) (a) 0% (b) 25% (c) 50% (d) 75% (e) 100% (f) none of the above ix. Memory Accesses: 0, 0, 4, 0 The Miss Rate is: (a) 0% (b) 25% (c) 50% (d) 75% (e) 100% (f) none of the above 'c' but it will be 'a' with large number of times