A body travelling with uniform acceleration crosses two points A and B with velocities $20\;ms^{-1}$ and $30 \;ms^{-1}$ respectively . The speed of the body at the mid-point of A and B is

Question

$\begin{array}{1 1} 24\;ms^{-1} \\ 25\;ms^{-1} \\ 25.5\;ms^{-1} \\10 \sqrt 6 \;ms^{-1}\end{array} $