You are being asked do draw four surfaces in different parts of a single figure. See the help for subplot() for examples. You could do a column of 4 plots, or a row of 4, or two rows of two, as shown below.
plot(x,x.^2); title('x squared');
plot(x,x.^3); title('x cubed');
plot(x,x.^4); title('x to the fourth');