Which type of research is most useful for purposes of prediction?

The tourism industry’s main job is to cater to customers who 1. travel for pleasure 2. seek the fanciest place to stay overnight 3. want an exquisite dining experience 4. desire to take part in a recreational activity.

Which of the following is an open question? "where are you from? " "when did you graduate from college? " "why did you leave your last job? " "do you have transportation to work? "

Coal combustion produces which of the following waste products? i. tar ii. methane iii. electricity i only ii only i and ii ii and iii i, ii, and iii