Question
Which of the following cannot be valid assignment of probability for elements or outcomes of sample space s = $W_1, W_2,W_{3,} W_4, W_5, W_6, W_7.$
| Elementary events: | $W_1$ | $W_2$ | $W_3$ | $W_4$ | $W_5$ | $W_6$ | $W_7$ |
| 0.7 | 0.6 | 0.5 | 0.4 | 0.3 | 0.2 | 0.1 |