A runner is jogging at a steady 2.7 km/hr. When the runner is 7.7 km from the finish line, a bird begins flying from the runner to the finish line at 5.4 km/hr (2 times as fast as the runner). When the bird reaches the finish line, it turns around and flies back to the runner. How far does the bird travel? Answer in units of km.

b. After this first encounter, the bird then turns around and flies from the runner back to the finish line, turns around again and flies back to the runner. The bird repeats the back and forth trips until the runner reaches the finish line. How far does the bird travel from the beginning (including the distance traveled to the first encounter)? Answer in units of km.

Pleaseee help! thanks :D