Paula owns four separate activities. She elects not to group them together as a single activity under the appropriate economic unit standard. Paula participates for 130 hours in Activity A, 115 hours in Activity B, 260 hours in Activity C, and 100 hours in Activity D. She has one employee, who works 125 hours in Activity D. Activities A, B, & C each require one employee who works 50 hours a year. Classify each activity as active or passive and explain your answers.