Create 3 subplots of the function

y = a sin( omega * t + phi). 

In the first subplot keep a = 0.1 and phi =0.5 and show the three curves obtained for
omega = 0.1, 1.0, and 5.0.

In the second subplot keep omega = 1 and phi =0.5 and show the three curves obtained for
a = 0.1, 2.0, and 6.0.

In the third subplot keep a = 1 and omega = 1 and show the three curves obtained for
phi = 0.1, 0.5, and 2.0.