The mass number of an element is equal to
a) the total number of electrons
b) the sum of the protons and neutrons
c) less than twice the atomic number
d) a constant number for the lighter elements

What did kublai khan learn from the chinese advisers he consulted?

Why were chinese american immigrants frequently detained when trying to immigrate through angel island? the rules for immigration were stricter at this checkpoint due to health issues that were prevalent among asian populations at this time. the location of the island was difficult to reach, and ships to the mainland were often prevented from sailing more than once a week. immigration agents were notorious for asking immigrants confusing questions as a means of denying them entry. low wages caused a shortage of immigration officials, so many immigrants had to wait weeks or months before their applications were processed.

What is the waterway that links the atlantic and pacific ocean