$300 \text{ g}$ of water at $25^{\circ} \text{C}$ is added to $100 \text{ g}$ of ice at $0^{\circ} \text{C}$. The final temperature of the mixture will be (in $^{\circ} \text{C}$)

$A$ conducting circular loop is placed in a uniform magnetic field,$B = 0.025 \, T$,with its plane perpendicular to the magnetic field. The radius of the loop is made to shrink at a constant rate of $1 \, mm/s$. The induced $e.m.f.$ when the radius is $2 \, cm$ is

The radius of the smallest electron orbit in a hydrogen-like ion is $(0.51 \times 10^{-10} / 4) \text{ m}$. This ion is:

Doping silicon with boron produces a

If $A, B$,and $C$ are three sets,then $A - (B \cup C)$ is equal to

Which of the following types of intercellular junctions helps in the passage of small molecules and ions?