Why do some plants have large, sweet-smelling flowers with sweet nectar?

How many continents are ther?

The vacuum of space may be emptier than the best vacuum that we can make with current technology, but it is not completely empty; every cubic centimeter of the emptiest parts of space contains about one atom.

What is the significance of the 2000s B. C

Because of its proximity tot the ring of fire, Southeast Asia often is threatened by massive and destructive waves

What happens to the birth rate of a country when the economy develops? Why?

What is one advantage of free trade?

Explain how the shading of the direct light of the sun causes a lunar eclipse.

Describe how modern science operates and distinguish it from philosophy, pseudoscience, and religion. In recognition of these distinctions, what individual (s) and methods mark the beginning of Astronomy as a science?

What two tectonic plates caused the Himalayan mountains

The longest mountain range in North Africa is what?