Question

Which waves arrive at a seismograph first? a. P waves b. S waves c. transverse waves d. surface waves

Answer 1

I believe the answer is a, primary waves 

Answer 2

Answer:

The P wave is designated the primary preliminary wave because it is the first to arrive at a seismic station after an earthquake. It travels at a speed usually less than 6 kilometers per second in the Earth's crust and jumps to 13 kilometers per second through the core.

Explanation: