$\int_{-\frac{\pi}{2}}^{\frac{\pi}{2}} \log \left(\frac{2-\sin \theta}{2+\sin \theta}\right) d \theta$ is equal to

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

Which of the following minerals is not remobilized in plants?

$A$ small source of sound vibrating at a frequency $500 ~Hz$ is rotated along a circle of radius $\frac{100}{\pi} ~cm$ at a constant angular speed of $5 ~revolutions ~per ~second$. The minimum and maximum frequency of the sound observed by a listener situated in the plane of the circle is (speed of sound is $332 ~ms^{-1}$).

In the following circuit,find $I_1$ and $I_2$.

Two of the lines represented by the equation $a y^4+b x y^3+c x^2 y^2+d x^3 y+e x^4=0$ will be perpendicular,then