What is the correct way to write the postal abbreviation for the state of Pennsylvania

Astronomers now classify pluto as really just a large member of

2 cycleists, 90 miles apart starting riding toward each other at some times one cycles twice as fast as the other if they meet 2 hrs later at what average speed is each cyclist traveling

Explain what a compound is

A mixture is red, you can see through it but the particles settle out. what type of mixture is it

A 2.0 kilogram rifle initially at rest fires a 0.002 kilogram bullet. As the bullet leaves the rifle with a velocity of 500 meters per second, what is the momentum of the rifle - bullet system?

If a person lives in china in which two hemispheres does he or she live

When the air in a submarine's huge air tanks is decompressed and it displaces the water in the ballast tanks with air, what does the submarine do? A. It sinks B. It floats C. It provides air to the passengers

The decomposition of a substance by an electric current is called

Along some shorelines, incoming waves cause the water to simply rise and fall rather that form a surf zone. What does this tell you about these shorlines?

Which word best describes the rate at which work is done? work energy power velocity