Treatement of sale of revalued land

I think you have to do indexation of the land, find current value and show gain or loss on the sale. I dont understand how lower of carrying amount and fvlcs is applicable here. Maybe it is still measured that way and record gain or loss over it. 

Plus, you have to close the revaluation account and offset the surplus or deficit with similar clasz of assets revalutuon gain and loss. So inde  the land, nrv is 60 and report gain or loss. Then finally deal with revaluation account