Read the following paragraph and answer the questions given below: The quantity of ¹⁴C as well as that of ¹⁴CO₂ present in the atmosphere remains constant. The concentration of ¹⁴C in all living organisms remains almost constant during their life time. After their death, ¹⁴C is not taken up by them but the content of ¹⁴C assimilated begins to decay by emitting p-particles, with half-life period of 5568 years. The decay rate at the time of death of plant is 16.1 counts per minute per gram of carbon. Hence, by measuring the decay rate of the dead matter, the age of matter can be calculated, e.g. if decay rate of sample of wood is found to be N disintegrations per minute per gram of carbon after t years, then where= disintegration constant and N₀ = number of disintegrations per minute per gram when the plant had just died.

1. ¹⁴C is present in environment because of

In a dead plant, the decay rate will be

¹⁴C is

The basis for carbon-14 dating method is that the