6. The discrete random variable \(X\) can take only the values 2,3 or 4 . For these values the cumulative distribution function is defined by
$$F ( x ) = \frac { ( x + k ) ^ { 2 } } { 25 } \text { for } x = 2,3,4$$
where \(k\) is a positive integer.
- Find \(k\).
- Find the probability distribution of \(X\).