Evaluate the determinant: $\left|\begin{array}{cc}2 & 4 \\ -5 & -1\end{array}\right|$

$A$ column of water within xylem vessels of tall trees does not break under its weight because of

In which disease does fluid accumulate in the alveoli and bronchioles?

The surface of a metal is illuminated with light of $400\, nm$. The maximum kinetic energy of the ejected photoelectrons was found to be $1.68\, eV$. The work function of the metal is.......$eV$ $(hc = 1240\, eV\, nm)$.

If the line $2x - 3y + 5 = 0$ is the perpendicular bisector of the line segment joining $(1, -2)$ and $(\alpha, \beta)$,then $\alpha + \beta =$