The rate mainly effects the size of the crystals in the rock forming
The porcupine is a rodent with an unusual trait. Porcupines have sharp spines or quills that help protect it against its predators. This trait is different from other rodents because of its needle like quills. This animal is also similar to that of a hedgehogs.
Answer:
A
Explanation:
they are associated with venous sinuses.this valve open one way flow of direction of the heart.
