In the given progressive wave equation,what is the maximum velocity of the particle? $Y = 0.5 \sin(10\pi t - 5x) \text{ cm}$

The rope shown at an instant is carrying a wave travelling towards the right,created by a source vibrating at a frequency $n$. Consider the following statements:
$I.$ The speed of the wave is $4n \times ab$
$II.$ The medium at $a$ will be in the same phase as $d$ after $\frac{4}{3n} \text{ s}$
$III.$ The phase difference between $b$ and $e$ is $\frac{3\pi}{2}$
Which of these statements are correct?

The figure below shows the wave $y = A \sin (\omega t - kx)$ at any instant traveling in the $+ve$ $x$-direction. What is the slope of the curve at $B$?

Two waves are represented by the equations $y_1 = a \sin \omega t$ and $y_2 = a \cos \omega t$. The first wave is .....

The equation of a wave is $Y = 6 \sin(12 \pi t - 0.02 \pi x + \frac{\pi}{3})$,where $x$ is in $m$ and $t$ is in $s$. The velocity of the wave is: (in $m/s$)

$A$ wave motion has the function $y = a_0 \sin(\omega t - kx)$. The graph in the figure shows how the displacement $y$ at a fixed point varies with time $t$. Which one of the labelled points shows a displacement equal to that at the position $x = \frac{\pi}{2k}$ at time $t = 0$?