A technician directs monochromatic light toward a single slit in an opaque barrier. The light has a wavelength of 500 nm and the slit is 0.180 mm wide. The light that passes through the slit creates a diffraction pattern on a screen, which is 1.60 m from the slit. (a) How wide (in mm) is the central maximum (the central, bright fringe), as measured on the screen?
mm
(b) How wide (in mm) is either of the two first-order bright fringes, as measured on the screen?
mm

Uranium has two naturally occurring isotopes. 238u has a natural abundance of 99.3% and 235u has an abundance of 0.7%. it is the rarer 235u that is needed for nuclear reactors. the isotopes are separated by forming uranium hexafluoride uf6, which is a gas, then allowing it to diffuse through a series of porous membranes. 235uf6 has a slightly larger rms speed than 238uf6 and diffuses slightly faster. many repetitions of this procedure gradually separate the two isotopes. what is the ratio of the rms speed of 235uf6 to that of 238uf6? express your answer to five significant figures.