Write a script called 'prob1.m' that solves for the variables y, and z in terms of a user inputed x. The variables y and z are defined as follows:

y = x - 30                when 0 < x < 100

= 0.20*x + 800       when x > 100

= -50                   otherwise

z = -1                 when x < 0

=  0                   when x = 0

=  1                   when x > 0

Your script should prompt the user to input a value of x (use the input function). Next it should compute the values of y and z (surpress the output at first). Finally it should explicitly display the values of x, y, and z. From with the 'hw4.m' script call 'prob1.m'.