Microeconomics Question?

the profit would be $6,000,000 and the quatity would be 6,000. South Africa's profit would decrease because according to the table, the more diamonds being produced the price decreases. However, i do want to point out that if South Africa and Russia only had a quantity of 6 or 7,000 diamonds they would maximize their profits to $21,000,000. So therefore in that case they would want to only produce either 3,00 or 3,500 diamonds a piece...