Final answer:
The peak acceleration of the elevator can be calculated using the difference in scale readings and the weight of the student.
Step-by-step explanation:
In this scenario, the scale reading on the bathroom scale initially reads 800 N and then increases to 950 N as the elevator ascends. The difference in scale readings is caused by the acceleration of the elevator. When the elevator accelerates upwards, it exerts an additional upward force on the student, causing the scale reading to increase. The peak acceleration of the elevator can be calculated using the difference in scale readings and the weight of the student.