$A$ ball is thrown downward with some initial velocity into a viscous liquid. Which of the following curves represents the correct variation of velocity versus time?

In an experiment,a small steel ball falls through a liquid at a constant speed of $10\, cm/s$. If the steel ball is pulled upward with a force equal to twice its effective weight,how fast will it move upward? ......... $cm/s$

In the experiment for measurement of viscosity $\eta$ of a given liquid with a ball having radius $R$,consider the following statements.
$A.$ Graph between terminal velocity $V$ and $R$ will be a parabola.
$B.$ The terminal velocities of different diameter balls are constant for a given liquid.
$C.$ Measurement of terminal velocity is dependent on the temperature.
$D.$ This experiment can be utilized to assess the density of a given liquid.
$E.$ If balls are dropped with some initial speed,the value of $\eta$ will change.
Choose the correct answer from the options given below:

The unit of the coefficient of viscosity in the $S.I.$ system is

The terminal velocity of a small-sized spherical body of radius $r$ falling vertically in a viscous liquid is given by the proportionality:

$A$ sphere of radius $r$ and density $\rho$ is dropped from a height $h$. When it falls into water,it attains a terminal velocity. If the coefficient of viscosity of water is $\eta$,then $h =$