Geologists have learned that Earth's interior is composed of layers by studying? a)the presence of fossils in Earth's crust
b)the size of volcanoes
c)the speed and path of seismic waves as they travel through Earth
d)the pattern of earthquakes that occurs on Earth's surface

The basketball coach tells his team to run sprints back and forth across the court, which is 30 m long. they start at the left end of the court, run back and forth 6 times, then end back at the left end of the court where they began. what distance did they run? what is their displacement?