Answer:
B. An electric current into a magnetic field
Explanation:
The generation of electrical power requires relative motion between a magnetic field and a conductor. In a generator, mechanical energy is converted into electrical energy. The electricity produced by most generators is in the form of alternating current.
Answer:

Explanation:
Static friction occurs when an object initially starts at rest. When the surfaces of the materials touch, the microscopic unevenness interlock greatest with each other, causing the most friction out of the three.
During sliding friction, an object is already moving or in motion. The microscopic surfaces still interlock, but because the object is in motion, it has a momentum. Therefore, the magnitude of sliding friction is less than that of static friction.
Rolling friction occurs when an object rolls across some surface. Rather than surfaces interlocking, rolling friction is caused by the constant distortion of surfaces. As it rolls, the surfaces of the object are constantly wrapping and changing. This distortion causes the rolling friction. However, it is much less in magnitude when compared to static or sliding friction.
galactic disk
The galactic disk is a thinned, leveled out distribution of stars which includes the typical to the largest and brightest. The Sun is in the Milky Way and lies amongst the majority of the stars where it bulges.
Answer:
(D)
to establish an understanding of key concepts relating to population biology
Explanation:
Thats what I would go with but I didn't read the article so I don't know what context was used. Good luck! :)
The correct answer is A, 2x^3 - x^2 +3x +7