8. We undertook a new code for calculating the number of hours required. In this sentence, the word "undertook" is used to indicate that the action of developing a new code was taken on by someone or a group of people. 9. We propose this study to… In this sentence, the word "propose" is used to indicate that the study is being suggested or put forward as an idea. 10. Within the framework of these criteria, we propose to… In this sentence, the phrase "the framework" refers to the set of criteria or guidelines that are being used to evaluate or guide the proposed action. 11. Defining P and Q falls outside the scope of this article. In this sentence, the phrase "the scope" refers to the range or extent of what is being discussed or considered in the article. The action of defining P and Q is beyond the boundaries or limits of what is being covered in the article. 12. It is aimed at students of engineering. In this sentence, the phrase "aimed at" is used to indicate that the target audience or intended group of people for the subject or topic is students of engineering. The purpose or goal of the subject is to specifically address or cater to this group.