Please explain to get those numbers by showing the formula and explain why

Exercise 13.16 REVALUATION MODEL KAS On 1 July 2013, Peewee Ltd acquired two assets within the same class of plant and equipment Information on these assets is as follows: Cost Expected useful life Machine A 100 000 5 years Machine B 60 000 3 years The machines are expected to generate benefits evenly over their useful lives. The class of plant and equipment is measured using fair value. At 30 June 2014, information about the assets is as follows: Fair value Expected useful life S 84 000 Machine A 4 years Machine B 38 000 2 years On 1 January 2015, Machine B was sold for S29 000 cash. On the same day, Peewee Ltd acquired Machine C for S80 000 cash. Machine C has an expected useful life of 4 years. Peewee Ltd also made a bonus issue of 10 000 shares at $1 per share, using S8000 from the general