Name the two vitamins which are added in the poultry feed.

What is the advantage of green manure?

For good production of poultry birds,what kind of management practices are important?

The ration (daily food requirement) for broilers is carbohydrate-rich with adequate minerals.

While selecting a breed of crop,which characteristics of the crop are to be taken into account by the farmers?

$A$ teacher mentioned organisms that enrich the soil with nutrients. Rahila was curious to know more about them. She searched the internet and learned about $Rhizobium$ bacteria and cyanobacteria.
$(i)$ What are bio-fertilizers?
$(ii)$ Explain how any one of the organisms mentioned above enriches the soil with nutrients.
$(iii)$ Why was Rahila curious to get more information?