How many electrons can fit in the orbital for which $n = 3$ and $l = 1$?

Which one of the following kinds of animals are triploblastic?

Amongst the given taxonomic aids,how many are associated with the preservation of specimens? Monograph,Flora,Key,Museums,Botanical Gardens,Catalogue,Herbarium,Manual

An electron microscope is operated at $40 \ kV$. The ratio of the resolving power of this microscope to another one which uses yellow light of wavelength $6 \times 10^{-7} \ m$ is:

The colour of hydrogen is

Electric charges $q, q, -2q$ are placed at the corners of an equilateral triangle $ABC$ of side $l$. The magnitude of the electric dipole moment of the system is