a) Use the two-dimensional diffraction relationship n = d*sin(theta) to calculate the groove spacing, d. Be careful with units, a good tip is to work in meters.
b) Calculate the number of grooves per centimeter for your grating. Hint: if the groove spacing was 0.1 ft, then how many grooves would you have per foot?
c) Suppose you were given the exact setup described in section A, expect that a different grating with fewer grooves/cm was used. How would you expect this to affect the location of the first-order spot? (Explain how you arrived at your conclusion