Answer
17kg of total mass is being accelerated by force F.
Work Step by Step
The force is pushing all the blocks together, so the mass of all the blocks combined is the total mass that is being accelerated.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.