If a convex lens of focal length $80 \ cm$ and a concave lens of focal length $50 \ cm$ are combined together,what will be their resulting power?

Match the items given in Column $I$ with those in Column $II$ and select the correct option given below:

Column $I$	Column $II$
$(a)$ Tidal volume	$(i)$ $2500 - 3000 \ mL$
$(b)$ Inspiratory Reserve volume	$(ii)$ $1100 - 1200 \ mL$
$(c)$ Expiratory Reserve volume	$(iii)$ $500 - 550 \ mL$
$(d)$ Residual volume	$(iv)$ $1000 - 1100 \ mL$

If $\vec{a}, \vec{b}$ and $\vec{c}$ are vectors with magnitudes $2, 3$ and $4$ respectively,then the best upper bound of $|\vec{a}-\vec{b}|^2+|\vec{b}-\vec{c}|^2+|\vec{c}-\vec{a}|^2$ among the given values is

A prism of angle $75^\circ$ and refractive index $\sqrt{3}$ is coated with thin film of refractive index $1.5$ only at the back exit surface. To have total internal reflection at the back exit surface the incident angle must be . . . . . . .
$(\sin 15^\circ = 0.25$ and $\sin 25^\circ = 0.43)$

Which of the following statements is incorrect for physical adsorption?

Which one of the following symbols and its representation,used in human pedigree analysis is correct?