12. which of the following accurately describes semiconductor diodes?
a. point-contact diodes are more likely to be used as rectifiers than junction diodes.
b. unlike junction diodes, point-contact diodes are enclosed in a suitable casing and have terminals for connecting them to a circuit.
c. unlike point-contact diodes, junction diodes utilize a point of metal wire in contact with a single wafer of p-type or n-type material.
d. junction diodes are preferred over point-contact diodes for most purposes.

Answer;

D. Junction diodes are preferred over point-contact diodes for most purposes.

Junction diodes are preferred over point-contact diodes for most purposes; accurately describes semiconductor diodes.

Explanation;

-Semiconductor diodes are specialized electronic components with two electrodes called the anode and the cathode, that are made with semiconductor materials such as silicon, germanium, or selenium.

-Point contact diode is formed by touching a metallic wire with an N-type semiconductor to form a small area of contact.

-A p-n junction diode is two-terminal or two-electrode semiconductor device, which allows the electric current in only one direction while blocks the electric current in opposite or reverse direction. Junction diodes are preferred over point-contact diodes for most purposes.

c.is a substance that requires a small amount of energy per gram to raise its temperature; has strong cohesive forces between molecules.

explanation:

a colorless, transparent, odorless liquid that forms the seas, lakes, rivers, and rain and is the basis of the fluids of living organisms.

28. evolution

29. environment, survive, offspring  

explanation: