** Solving Physics Story Problems**

By combining the techniques we have discussed with a simple English parser, a remarkably small Lisp program can solve physics problems stated in English:

>(phys '(what is the area of a circle with radius = 2)) 12.566370614359172 >(phys '(what is the circumference of a circle with area = 12)) 12.279920495357862 >(phys '(what is the power of a lift with mass = 5 and height = 10 and time = 4)) 122.583125