When earthquakes occur, seismic waves are sent through the Earth. The two most common types of seismic waves are P waves and S waves. The graph below shows how P waves and S waves can travel through Earth. Modified from image courtesy of USGS

Based on the graph, what is true about P waves and S waves?
A.
They travel at the same speed through the Earth.
B.
They travel at different speeds through the Earth.
C.
They both travel faster than 7,000 miles per minute.
D.
They both travel slower than 1,000 miles per hour.

20 brainliest for whoever answers correctly and answers all choose the statements that accurately describe china's "one child policy." china's "one child policy" began as soon as the communists came to power. the "one child policy" was meant to keep the population from reaching 700 million. the "one child policy" was meant to slow china's population growth. the "one child policy" began as a result of the country's war with japan. some people were allowed to have more than one child. the "one child policy" began in 1979. the "one child policy" was most enforced in urban areas. the "one child policy" ended at the start of 2016. china's population is current just under 1 billion people.

Ateam of researchers calculates that a glacier will melt completely away in the next 100 years. which land structure will most likely be left behind after the glacier melts?

These factors threaten north americas ecosystems