Which of the following reagents is used to distinguish acetone and acetophenone?

The products formed when diethyl ether is reacted with cold $HI$ are

The point $P$ is equidistant from $A(1, 3)$,$B(-3, 5)$,and $C(5, -1)$. Then $PA$ is equal to:

Human urine is usually acidic because

If a ladder weighing $250 \ N$ is placed against a smooth vertical wall and the coefficient of friction between the ladder and the floor is $0.3$,what is the maximum force of friction available at the point of contact between the ladder and the floor?

The area (in sq unit) of the region bounded by the curves $2x = y^2 - 1$ and $x = 0$ is