Classify each random variable as discrete or continuous.
a. The number of visitors to the Museum of Science in Boston on a randomly selected day.
b. The camber-angle adjustment necessary for a front-end alignment.
c. The total number of pixels in a photograph produced by
a digital camera.
d. The number of days until a rose begins to wilt after purchase from a flower shop.
e. The running time for the latest James Bond movie.
f. The blood alcohol level of the next person arrested for DUI in a particular county.