A woman places a laser pointer on the ground and shines it at the top of a lamp post. She then stands between the laser and the lamp post so the laser just barely touches the top of her head. The woman, the lamppost, the laser, and the ground combine to form two similar right triangles. She is standing 2.4 meters away from the lamppost and 2.1 meters from the laser. If the woman is 1.8 meters tall, how tall is the lamppost? 3.9 meters
2.1 meters
1.6 meters
3.4 meters