Solve the following problem given below:
Problem: For a demonstration, a professor uses a razor blade to cut a thin slit in a piece of aluminum foil. When she shines a laser pointer (Lambda=680nm) through the slit onto a screen 5.5m away, a diffraction pattern appears. The bright band in the center of the pattern is 8.2cm wide.
Part I: What is the width of the slit?
I am need of complete solution for this problem please help- me out to get right solution and express your answer using two significant figures.