"consider the hospital emergency room data displayed below. let a denote the event that a visit is to hospital 4, and let b denote the event that a visit results in lwbs (at any hospital). determine the following probabilities. round to three decimal places. a) p( a and b )b) p(a')c) p( a u b)d) p(a u b)e) p(a' and b')table: 1 2 3 4total 5297 6993 5638 4343 22271 lwbs 199 277 249 249 974 admitted 1274 1550 662 987 4473 not admitted 3824 5166 4727 3107 16824