Who classified all Bryophytes into three classes?

What is the output $Y$ in the following circuit,when all the three inputs $A, B, C$ are first $0$ then $1$?

From the ground state electronic configuration of the elements given below,pick the one with the highest value of second ionisation energy.

$A$ gas is compressed isothermally to half its initial volume. The same gas is compressed separately through an adiabatic process until its volume is again reduced to half. Then

Which of the following is a characteristic of monocots?

Match the following columns:

Column-$I$	Column-$II$
$(a)$ Gymnosperms	$(p)$ Trimerous flowers
$(b)$ Monocots	$(q)$ Absence of flowers
$(c)$ Dicots	$(r)$ Primitive flowers
$(d)$ Pteridophytes	$(s)$ Tetramerous or pentamerous flowers