Which class of algae do they belong to?

Which class of Pteridophyta does a horsetail belong to?

To which subsets of R do the followings belong? sqrt7 ,3/5,0,15,-6,10

To which colloidal system does milk belong?

Given below are the pairs of animals and phylum which they belong to. Which out of these is not a matching pair and why? Taenia (Tapeworm) - Platyhelminthes Pheretima (Earthworm) - Annelida Asterias (Starfish) - Mollusca Adamsia (Sea anemone) - Coelenterate

What are root hairs? Which region of the root do they arise from? What is their function?

What do the symbols : Br,