What is empiricism and how is a priori knowledge a challenge to this view?

Empiricism is when one’s knowledge of the world is based on their experiences. A priori knowledge is a challenge to this view by knowledge being received not by experiences

Which eman that people who believe in empiricism would see knowledge as something that could only be gotten through our sensory experience while people who believe in priori knowledge tend to believe that knowledge can be transferred through genetics.

you would times this by how many days there are in a year 365*400=$146000