Biological assets

Scottson, a farmer, acquired 600 two-year old cows on 1 January 20X1 for $800 each. 100 calves were born in December 20X1. 150 animals were sold during the year for $840 each. The fair value less costs to sell the cows at 31 December 20X1 was: Calves $200 Two-year old cows $850 Three-year old cows $900

How much should be recognised in profit or loss in total in respect of the cows for the year ended 31 December 20X1?

I don’t know what is the correct answer.

I did the sum like this. But I don’t know whether my answer is right or wrong.

1 January 20X1 2 year old cows (600 * 850) : 510000
December 20X1 Calves born (100 * 200) : 20000

Total : 530000

31 December 20X1 3-year-old cows (450 * 900): 405000 (600 – 150 (sold) = 450)
Calves (100 * 200): 20000
Total : 425000

Gain to SPL : 105000 (530000 – 4250000)

I also have confusion if I have to take the fair value less cost to sell value of calves to recognize profit or loss.