On her vacations Veena visits four cities `(A , B , C a n d D)`in a random order. What is the probability that she visits(i) A before B?(ii) A before B and B before C?(iii) A first and B last?(iv) A either first or second?(v) A just be

Explanation

To solve the problem, we will analyze each part step by step.

### Given:
Veena visits four cities: A, B, C, and D in a random order.

### Total Arrangements:
The total number of arrangements of the four cities is given by the factorial of the number of cities:
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