A wave is described by the equation

A wave is described by the equation

$y=(1.0 \mathrm{~mm}) \sin \pi\left[\frac{\mathrm{x}}{2.0 \mathrm{~cm}}-\frac{\mathrm{t}}{0.01 \mathrm{~s}}\right]$

a. Fin the time period and the wave length.

b. Write the equation for the velocity of the particles. Find the speed of the particle at $x=1 . p \mathrm{~cm}$ at the time $t=0.01 \mathrm{~s}$

c. What are the speeds of the particles at $x=3.0 \mathrm{~cm}, 5.0 \mathrm{~cm}$ and $7.0 \mathrm{~cm}$ at $t=0.01 \mathrm{~s}$ ?

d. What are the speeds of the particle at $x=0.011,0.012$ and $0.013 \mathrm{~s}$ ?