Which of the following is the most stable conformer of butane?

$A$ cricketer can throw a ball to a maximum horizontal distance of $100 \, m$. The speed with which he throws the ball is (to the nearest integer) (in $m/s$).

When alcohol vapor is passed over heated reduced copper $(Cu)$,the alcohol is converted into an alkene. Which type of alcohol is this?

The correct formula of diammine dichlorodicyanochromate$(III)$ ion is

The only taxonomic category that has a real existence is...

Let $P$ be a plane passing through the points $(2,1,0)$,$(4,1,1)$ and $(5,0,1)$ and $R$ be the point $(2,1,6)$. Then the image of $R$ in the plane $P$ is