In a survey of college students, each of the following was found. Of these students, 353 owned a tablet, 293 owned a laptop, 284 owned a gaming system, 193 owned a tablet and a laptop, 200 owned a tablet and a gaming system, 140 owned a laptop and a gaming system, 69 owned a tablet, a laptop, and a gaming system, and 28 owned none of these devices. Complete parts a) through e) below:

a) How many college students were surveyed? (Simplify your answer.)
b) Of the college students surveyed, how many owned a tablet and a gaming system, but not a laptop? (Simplify your answer.)
c) Of the college students surveyed, how many owned a laptop, but neither a tablet nor a gaming system? (Simplify your answer.)
d) Of the college students surveyed, how many owned exactly two of these devices? (Simplify your answer.)
e) Of the college students surveyed, how many owned at least one of these devices? (Simplify your answer.)