$Casuarina$ $equisetifolia$ is a

Which of the following groups of plants produces economically useful fibers?

Identify the correct terms for the following analogy-based questions:
$(i)$ Sunflower : Alternate phyllotaxy :: Alstonia : ...........
$(ii)$ Datura : Actinomorphic flower :: Bean : ............

How many plants in the list given below have marginal placentation: Mustard,Gram,Tulip,Asparagus,Arhar,Sun hemp,Chilli,Colchicum,Onion,Moong,Pea,Tobacco,Lupin?

Which of the following is not a stem modification?

Which of the following is a characteristic of a dicotyledonous plant?