Use the Following Information for Questions

Short Answer

Use the following information for questions:
A group of 50 students had their blood pressures measured before and after watching a movie containing violence. The mean blood pressure before the movie is to be compared with the mean pressure after the movie. In general, blood pressure increases by 5 points after watching something violent happening with a standard deviation of 7 points.
-What is the standard deviation of the sampling distribution of the sample mean difference in blood pressure before and after watching a movie containing violence?