Which is the major product of the following reaction?

The area (in sq. units) of the region described by $\{(x,y): y^2 \le 2x \text{ and } y \ge 4x - 1\}$ is

Two sources $A$ and $B$ are sending notes of frequency $680 \, Hz$. A listener moves from $A$ towards $B$ with a constant velocity $u$. If the speed of sound in air is $340 \, ms^{-1}$, what must be the value of $u$ so that the listener hears $10$ beats per second (in $ \, ms^{-1}$)?

In a $\triangle ABC$,if $\angle C = 90^{\circ}$,then $\frac{a^2-b^2}{a^2+b^2}$ is equal to

An increase in pressure required to decrease the $200\,L$ volume of a liquid by $0.004\%$ in a container is ........... $kPa$. (Bulk modulus of the liquid $= 2100\,MPa$)

An electron makes a transition from orbit $n = 4$ to the orbit $n = 2$ of the hydrogen atom. The wave number of the emitted radiation ($R =$ Rydberg's constant) will be