The exterior temperature increases steadily. (Apex) ^-^
The answer is A. a light wave
C and D both need water as a medium and sound needs air to vibrate in order to travel. light, on the other hand, does not need a medium
It's Gametes Sexual reproduction is the union of male and female gametes to form a fertilized egg, or zygote. The resulting offspring inherit one half of their traits from each parent.
They drill holes and bring up samples of rock and study how seismic wave move through the earth.