I do not have access to specific exercise questions from 9th-grade science textbooks as these vary widely depending on the curriculum, textbook edition, and teaching style. However, based on common topics covered in the first lesson of 9th-grade science, here are examples of the types of exercise questions you might encounter:

• Multiple Choice Questions:
  Which of the following is the correct order of steps in the scientific method?
• True or False Questions:
  A hypothesis is a proven fact. (True/False)
• Short Answer Questions:
  Define the term 'independent variable' and give an example.
• Problem-Solving Questions:
  A student measures the length of a table three times and obtains the following measurements: 1.50 m, 1.52 m, and 1.49 m. Calculate the average length of the table.
• Open-Ended Questions:
  Explain the importance of having a control group in an experiment.

For specific exercise questions, please refer to your 9th-grade science textbook or ask your teacher.