Write the correct forms of the participles

1. The force
   [ ]
   on the object was measured.
2. [ ] from college, she began to work at a bank.
3. [ ] these experiments we can compare the weight of elements.
4. The substances
   [ ] in the experiment were described in the report.
5. [ ] to the lecture, students usually leave the class.
6. There are a couple of classes
   [ ] optionally.
7. A successful group project is a result of all the members
   [ ] together.
8. Describe the picture
   [ ] on the slide.