Solve this:

7. The table shows the number of people visited the 'Good - Living Pavilion 'in a trade fair during differen time of day:
 

Time	9am-11am	11am-1pm	1pm-3pm	3pm-5pm	5pm-7pm
No. of people	175	125	225	200	120

Find he probability that randomly chose peson visited the pavilion,

(a) After 1 pm but before 5 pm            ​(c) after 5 pm
(b) between 9 am to 1 pm                  (d) Between 3 pm and 5 pm.

Prove that the angle subtended by an arc at the centre of dauble of angle subtended by it.