In an agricultural experiment, a solution containing 1 mole of a radioactive material (t1/2 = 14.3 days) was injected into the roots of a plant. The plant was allowed 70 hours to settle down and then activity was measured in its fruit. If the activity measured was 1 μCi, what per cent of activity is transmitted from the root to the fruit in steady state?
n= 1mole = 6× 1023 atoms=N˳
Given, λ = 
According to Law of Radioactivity,
No. of radioactive sample at time t, 
N= 5.2× 1023 atoms
According to law of Radioactivity, activity of a radioactive isotope at time t is the no. of active nuclei at that time times disintegration constant of the decay process.
As 
Activity transmitted 
1