Saber” is knowing what something is
Conocer” is wanting to know what something is .
Hope it helps <3
The first one “El ciclismo”
For the first one, it's b) les
For the second one, it's a) le
It means:
What are the main causes of the sale of huachicol
El templo mayor es un sitio ceremonial que se construyó cerca de año 1325