In the two-slit interference experiment, the slit widths are each 12.0 mm, their separation is 24.0 mm, the wavelength is 600 nm, and the viewing screen is at a distance of 4.00 m. Let IP represent the intensity at point P on the screen, at height y = 70.0 cm. 

(a) What is the ratio of IP to the intensity Im at the center of the pattern? 

(b) Determine where P is in the two-slit interference pattern by giving the maximum or minimum on which it lies or the maximum and minimum between which it lies.

 (c) In the same way, for the diffraction that occurs, determine where point P is in the diffraction pattern.