What are three ways we use natural resources?

What was the direct cause of the u.s. entry into world war ii? a. the bombing of pearl harbor b. the invasion of poland by germany c. the capture of belgium by germany d. the battle of britain

Bonus question: according to wikipedia, in chinese philosophy yin and yang "describes how seemingly opposite or contrary forces may actually be complementary, interconnected, and interdependent." what are some examples from the story that amy tan may have intentionally incorporated elements of yin and yang philosophy into this story? select 2.

An object weighs 40n in air , weighs 20n when submerged jn water and 30n submerged in a liquid of unknown density .what is the density of the liquid?