Which of the following is the weakest base?

What are the approximate weight and diameter of $Rafflesia$ $arnoldii$?

$A$ point object is placed at a distance of $10\,cm$ and its real image is formed at a distance of $20\,cm$ from a concave mirror. If the object is moved by $0.1\,cm$ towards the mirror,the image will shift by about:

If $\alpha, \beta$ are the roots of the equation $x^2+bx+c=0$ and $\alpha+h, \beta+h$ are the roots of the equation $x^2+qx+r=0$,then $h$ is equal to

Which of the following alkenes does $NOT$ exhibit cis-trans isomerism?

If a polygon of $n$ sides has $275$ diagonals,then $n$ is equal to