Final answer:
Without knowing Adam's hourly wage, it is not possible to calculate the number of hours he needs to work to meet his goal of $3000, considering he has $690 saved.
Step-by-step explanation:
To determine how many hours Adam will need to work to reach his goal of $3000 when he has already saved $690, we must first understand that crucial information such as his hourly wage is missing. Without this key piece of data, we cannot accurately calculate the number of hours required to achieve the additional amount needed, which is $3000 - $690 = $2310. As such, it would be necessary to know how much Adam earns per hour to provide a valid answer to this question.
In the absence of this critical information, we cannot select the correct answer among the options provided: A) 20 hours, B) 30 hours, C) 40 hours, or D) 50 hours.