What mistake did I make on my homework please correct it for me

Answer (datum point);

Well, a and b together would be negative. b alone would also be negative.

The answer is c, i, iii, and iv. this is because farming and mining deal with harvesting raw materials, construction work falls under manufacturing, and piloting a plane is a service. ii is wrong because making bread is using  raw materials to produce goods, which would fall under the secondary sector, not primary.

I'm going to say it's 5-6 million