Answer:
C 15
Step-by-step explanation:
20÷4x3=15
Answer: 0.907
Step-by-step explanation:
The average rate of change in a function from x= a to x = b is given by :-

Given: 
Then, the average rate of change of the SAT score for students with household incomes ranging from $40,000 to $60,000 per year will be :

Hence, the average rate of change of the SAT score for students with household incomes ranging from $40,000 to $60,000 per yearr= 0.907