During interphase of what process, each chromosome is duplicated, and the sister chromatids formed during synthesis are held together at the centromere region by cohesin proteins?

The four Science Regents exams (Earth Science, Living Environment, Chemistry, and Physics) also include separately-scheduled lab practicals.
In New York, students have the opportunity to take Regents Exams in grades 9-12 and, when appropriate, in grade eight.