Perforated and electronically conductive semiconductor contact that conducts electric current in only one direction. It is called?

probably not if net force is zero

the entire statement is true and correct.  

there's no diagram, nothing is illustrated, and no question is asked.

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.

a. carbon monoxide from car exhaust

b.particulate matter, such as soot

c.water vapor from a factory smokestack

d.acid rain

these are the answer choices im on that question right now