Which of the following pairs of monosaccharides form sucrose?

Forelimbs of cat,lizard used in walking; forelimbs of whale used in swimming and forelimbs of bats used in flying are an example of

The resistance across $M$ and $N$ in the given figure is

When the gap is closed without placing any object in the screw gauge whose least count is $0.005 \ mm$,the $5^{th}$ division on its circular scale coincides with the reference line on the main scale. When a small sphere is placed,the reading on the main scale advances by $4$ divisions,whereas the circular scale reading advances by five times the corresponding reading when no object was placed. There are $200$ divisions on the circular scale. The radius of the sphere is .......... $mm$.

$A$ particle carrying a charge equal to $100$ times the charge on an electron is rotating per second in a circular path of radius $0.8 \ m$. The value of the magnetic field produced at the centre will be (where ${\mu _0}$ is the permeability of vacuum).

Let $R$ and $S$ be two relations on a set $A$. Then which of the following statements is true?