Sept.December 2019. Past paper FR

Hi there,
Hope you are all safe,

I have an issue with the question 31 a of the past paper September December 2019 about the inventory adjustments.

It states:

Inventory adjustment
The disposal of the inventory at a discounted price would be classified as an adjusting event in accordance with IAS® 10 Events
After the Reporting Period.
Retail price of the inventory $1·5 million; GP margin 20% = $0·3 million
Closing inventory (currently credited to SOPL) $1·2 million
A write down to NRV would require a $0·6m charge to cost of sales thereby increasing it to $70·6 million and reducing profit
from operations to $12·56 million. In the statement of financial position, inventory is written down to $3·36 million and
retained earnings will be adjusted to $32·28 million.

I am not so sure how do they find this NRV amount and how do they find this 0.6M to be charged in the SPL. I only assume that the question said: inventory were sold at 50% of what it had cost so then I would assume the 1.2 M at 50% gives me 0.6M.

If someone could explain it more in details?
Thanks