The ratio of carbon 14 to nitrogen-14 in an artifact is 13. Given that the half- life of carbon-14 is 5730 years, how old is the artifact?
A. 17,190 years
B. 22,920 years
C. 11,460 years
D. 5730 years

Ithink it is letter b, i may be wrong but i think that is the answer

Current supplied to consumers from generating plants like coal power plant, nuclear power plant, geothermal and others are in form of alternating current instead of direct current because it can be transported easily in a long distance. also, the alternating current has a wide range of frequency and the amount or energy can be increased or decreased.