A - choosing letter A first
Answer:
The student's mean score in the class is 80.6
Step-by-step explanation:
we know that
To find out the student's mean score in the class, multiply each score by its worth and adds the numbers

therefore
The student's mean score in the class is 80.6
It is right it is C 454.5
Answer: 1.25
Step-by-step explanation:
The explicit formula for the sequence is 
Substituting in n=4,

Well, the way I would do this is count the course and write that first, than put the 2 colins and than the carton of milk ratio. I hope this helped!