Which of the following is a transparent tissue?

$A$ uniform magnetic field $B$ exists in a cylindrical region of radius $10\, cm$ as shown in the figure. $A$ uniform wire of length $80\, cm$ and resistance $4.0\,\Omega$ is bent into a square frame and is placed with one side along a diameter of the cylindrical region. If the magnetic field increases at a constant rate of $0.010\, T/s$,find the current induced in the frame.

One end of a spring of force constant $k$ is fixed to a vertical wall and the other to a block of mass $m$ resting on a smooth horizontal surface. There is another wall at a distance $x_0$ from the block. The spring is then compressed by $2x_0$ and released. The time taken to strike the wall is

What is the product formed when salicylic acid is reacted with zinc dust?

$CrO_3$ dissolves in aqueous $NaOH$ to give: