(a) Write a macro DISP (f, x) that expands into a call of printf that displays the value of the function f when called with argument x. For example, DISP (sqrt, 3.0) should expand into print f ( "sqrt ( %g) %g ". 3 . 0, sqrt (3. 0) ) ; (b) Write a macro DISP2 (f, x, y) that's similar to DISP but works for functions with two arguments. 6. Please embed the two macros in a simple test program