The amino acid which is not optically active is

Given that,$a \alpha^2+2 b \alpha+c \neq 0$ and that the system of equations
$\begin{aligned} & (a \alpha+b) x+a y+b z=0 \\ & (b \alpha+c) x+b y+c z=0 \\ & (a \alpha+b) y+(b \alpha+c) z=0\end{aligned}$
has a non-trivial solution,then $a, b$ and $c$ lie in

If $b$ and $c$ are the lengths of the segments of any focal chord of a parabola $y^2 = 4ax$,then the length of the semi-latus rectum is:

The period of oscillation of a simple pendulum of length $l$ suspended from the roof of a vehicle, which moves without friction down an inclined plane of inclination $\alpha$, is given by

$A$ block of mass $0.50 \ kg$ is moving with a speed of $2.00 \ ms^{-1}$ on a smooth surface. It strikes another mass of $1.00 \ kg$ (initially at rest) and then they move together as a single body. The energy loss during the collision is .............. $J$

Who classified all Bryophytes into three classes?