Which of the following pairs acts as a biofertilizer?

$50 \Omega$ and $100 \Omega$ resistors are connected in series. This combination is connected to a battery of $2.4 \text{ V}$. When a voltmeter of $100 \Omega$ resistance is connected across the $100 \Omega$ resistor,the reading of the voltmeter will be .......... $\text{V}$.

The major product of the following reaction is:

The function $f(x)=\log (1+x)-\frac{2 x}{2+x}$ is increasing on

$\frac{\sqrt{2} \cos 45^{\circ}+\cos 56^{\circ}+\cos 58^{\circ}-\cos 66^{\circ}}{\sqrt{2} \cos 28^{\circ} \cos 29^{\circ} \sin 33^{\circ}} = $

The point $(3,-4)$ lies on both the circles $x^2+y^2-2x+8y+13=0$ and $x^2+y^2-4x+6y+11=0$. Then,the angle between the circles is