SMELTER	COUNTRY	COMPANY	CAPACITY	VARIABLE COST	FIXED COST
Sorocaba A	Brazil	Other	122	588	238
Zaporozhye	Ukraine	CIS	100	599	122
Grand Baie	Canada	Alcan	180	602	269
Arvida 1	Canada	Alcan	85	668	472
Alouette	Canada	Other	215	692	279
Irkutsk	Russia	CIS	260	712	126
Bratsk	Russia	CIS	850	757	138
Baie Comeau 1	Canada	Reynolds	159	779	390
Boyne Island	Australia	Comalco	244	807	225
Sao Luis	Brazil	Other	357	875	226
Valco	Ghana	Kaiser	200	887	194
Badin B	USA	Alcoa	57.5	920	319
Hannibal	USA	Other	245	946	332
Sundsvall 1	Sweden	Other	76.5	985	335
Lynemouth	UK	Alcan	130	1,024	308
Jebel Ali	Dubai (UAE)	State	245	1,061	88
Fushun 2	China	State	450	1,166	97
Inota	Hungary	State	33.65	1,271	196
Korba	India	State	100	1,518	100
Renukoot B	India	State	30	2,070	110

If these were the only aluminum plants in the world, the most aluminum that could possibly be produced would be their total capacity: 4139.65 tons.

How should we start figuring out what goes onor what should go onin this market? Let's think about who would produce aluminum at a given price.

What if worldwide demand were 4000 tons - which would be the "last" plant that produces in this case?

Fushun 2

Fushun 2, together with all the plants with lower variable costs, would bring worldwide production to 3976 tons.

Inota

The plants with variable costs less than Inota's can produce only 3976 tons. Inota is the last, most expensive plant necessary to reach 4000 tons of production.

Korba

4000 tons can be produced even if only plants with lower variable costs than Korba's are in action.

Renukoot B

4000 tons can be produced even if only plants with lower variable costs than Renukoot B's are in action.

Please explain how the answer is INOTA . What was I supposed to add together to get to 4000.