All starfish limbs are designed to do have the same function, which means that in case a limb is severed, the other arms can make up for it until the arm regrows, which it does after a while. They are all connected to the center of the starfish which should not be damaged.
There’s no diagraaaammmmm.
-10grade/week
Explanation:
Given parameters:
Initial grade = 95grade
Final grade = 65grade
Time = 3weeks
Unknown parameter:
Rate of change of grade = ?
Solution:
Rate is defined as the change of a quantity with time.
Rate of change of grade = 
Rate of change of grade =
= 
Rate of change of grade = -10grade/week
The rate of change of the student's grade is -10grade/week. It implies that the grade of the student reduces by 10unit per week.
Answer:
the environment and parasites