What is the empirical formula of the compound that contains 3.7% H,
44.4% C, and 51.9%N?

the answer to your question is c.

if you read the house of usher you should know that the house was haunted

why is arctic sea ice important? arctic sea ice keeps the polar regions cool and moderate global climate. sea ice has a bright surface; 80 percent of the sunlight that strikes it is reflected back into space. as sea ice melts in the summer, it exposes the dark ocean surface.

practical process described pest part of scientific investigation.

because practical knowledge is powerful then therotical knowledge.