You should yield the right-of-way:

• To drivers already on a highway when you are on the entrance ramp
• To the driver on your right at a four-way stop
• To other drivers when approaching an intersection with a Yield sign facing you
• All of the above
  Explanation:

  "You should yield the right-of-way to 1. Drivers that are already on the limited-access or interstate highway if you are on the entrance or acceleration ramp. 2. The driver on your right at a four-way intersection controlled by stop signs. 3. Other drivers, if you are approaching an intersection with a Yield sign facing you."