What is the approximate weight of the flower of $Rafflesia$ $arnoldii$ (in $kg$)?

The normal freezing point $(f.p.)$ of nitrobenzene is $278.82\, K$. If a non-volatile solute is dissolved in it and a solution of $0.25\, m$ (molality) is prepared,the observed $f.p.$ of the solution is $276.82\, K$. Evaluate $K_f$ of nitrobenzene in $K\, kg\, mol^{-1}$.

If the terminal speed of a sphere of gold (density $= 19.5 \,kg/m^3$) is $0.2 \,m/s$ in a viscous liquid (density $= 1.5 \,kg/m^3$),find the terminal speed of a sphere of silver (density $= 10.5 \,kg/m^3$) of the same size in the same liquid.

The probability that a number selected at random from the set of numbers ${1, 2, 3, \ldots, 100}$ is a cube, is

$A$ body is executing simple harmonic motion. At a displacement $x$ its potential energy is $E_1$ and at a displacement $y$ its potential energy is $E_2$. The potential energy $(E)$ at displacement $(x+y)$ is

Match the common name given in column $I$ with their taxonomic category order given in column $II$ and choose the correct combination from the options given below.

Column-$I$ (Common name)	Column-$II$ (Taxonomic category-Order)
$A$. Wheat	$I$. Primata
$B$. Mango	$II$. Diptera
$C$. Housefly	$III$. Sapindales
$D$. Man	$IV$. Poales