Which best describes why the Mayan Empire ended? A
The Spanish invaded
B
Many died of smallpox
С
They had a civil war
D
No one really knows

Can someone me answer all the questions?

What landform is circled in the map above?

What was piaget's explanation as to why preschool-age children in the preoperational stage make errors on tasks requiring conservation? a) preschool children's tendency toward centration prevents them from focusing on other relevant features of a situation b) preschool children have not yet developed numerical understanding; therefore, different amounts are meaningless c) preschool children's neural-visual network is not fully matured d) preschool children have not lived long enough and accrued enough experience to know the difference between quantities