If $A$ and $B$ are any two sets,then $A \cap (A \cup B)$ is equal to

Which of the following is $NOT$ included in the class of Bryophyta as classified by Rothmaler?

Write the resonance structures of $CO_3^{2-}$ and $HCO_3^-$.

Let $A = \{ (x, y) : y = e^x, x \in R \} $ and $B = \{ (x, y) : y = e^{-x}, x \in R \} $. Then

If $\frac{x^2+x+1}{x^2+2x+1} = A + \frac{B}{x+1} + \frac{C}{(x+1)^2}$,then $A-B$ is equal to

$A$ particle is moving along a circular path with constant speed and centripetal acceleration $a$. If the speed is doubled,the ratio of its acceleration after and before the change is