The plant body is differentiated into which of the following parts?

$A$ series combination of resistor $(R)$ and capacitor $(C)$ is connected to an $A$.$C$. source of angular frequency $\omega$. Keeping the voltage same,if the frequency is changed to $\omega / 3$,the current becomes half of the original current. Then the ratio of the capacitive reactance and resistance at the former frequency is

If $A$ and $B$ are square matrices of order $3$,$A$ is non-singular,and $AB = O$,then $B$ is a

The role of haemoglobin is to

Which of the following represents soap?

If the line $y=2x+c$ is a tangent to the circle $x^2+y^2=5$,then a value of $c$ is