The black board appears black because:
A. Black is absorbed by the board
B. The color black is reflected back to you by the board
C. All visible light wavelengths (ROYGBV) are absorbed by the board
D. All visible light wavelengths (ROYGBV) are reflected off the board

Many machines- including inclined planes such as ramps- increase the strength of the force put into the machine but decrease the distance over which the force is applied.

I'm thinking it's 2 you are asked to explain the earth's magnetic field. which is the best reply? 1. the earth's magnetic south is similar to the north pole of a magnet. 2. the earth's core has a strong magnetic charge similar to the south pole of a magnet. 3. the earth's geomagnetic south is similar to the south pole of a magnet. 4. the earth's magnetic charge is not centered at either pole; it varies based on location.

How many neutrons does plutonium -196 with an atomic number of 78.