13. The average weight of 8 persons in increased by 2.5 kg when one of them whose weight is 56 kg is replaced by a new man. The weight of the new man is :

14. The average of five results is 46 and that of the first four is 45. The fifth result is :

15. The average temperature of the first three days is 270 C and that of the next three is 290 C. If the average of the whole week is 28.50 C, the temperature of the last day of the week is :