Final answer:
Jenna saves $30 per week for a new car.
Step-by-step explanation:
To find Jenna's rate of change, we need to determine the amount she saves per week. Since she saves $60 every two weeks, we can divide $60 by 2 to find the amount she saves per week.
$60/2 = $30
Therefore, Jenna's rate of change is $30 per week. So, the answer is (b) $30 per week.