If $L = 2.331 \, cm$ and $B = 2.1 \, cm$,then $L + B = $ (in $, cm$)

$A$ metallic ring of radius $r$ and cross-sectional area $A$ is fitted into a wooden circular disc of radius $R$ $(R > r)$. If the Young's modulus of the material of the ring is $Y$,the force with which the metal ring expands is

Tracheids differ from other tracheary elements in

Keystone species deserve protection because these

The secretion from the abdominal glands of honey bees is ..........

Let $C$ be the circle with centre $(0,0)$ and radius $3$ units. The equation of the locus of the midpoints of the chords of the circle $C$ that subtend an angle of $\frac{2\pi}{3}$ at its center is: