A wave is given by the equation $y=(0.02) \sin (\pi x-8 \pi /$ then the velocity of the wave is $(y$ and $x$ are in metre and $t$ is in second)

A cylindrical tube open at both ends has a fundamental frequency $f$ in air. The tube is dipped vertically in water, so that half of it is in water. The new fundamental frequency is

Which of the following wave has the largest wave speed?

A wire of length 0.4 m stretched at both ends vibrates 250 times per second. If the length of the wire is increased by 0.1 m and the stretching force is reduced to $1 / 4$ th of its original value, then the new frequency is