Sixteen cards are labelled as $\mathit{a},\mathit{b},\mathit{c}.......\mathit{m},\mathit{n},\mathit{o},\mathit{p}$. They are put in a box and shuffled. A boy is asked to draw a card from the box. What is the probability that the card drawn is:
(i) a vowel.
(ii) a consonant.
(iii) none of the letters of the word median.