`50%` of a radio active substance decays in `5` hours. The time required for the `87.5%` decays is

50% of the amount of a radioactive substance decomposes in 5 years. The time required for the decomposition of 99.9% of the substance will be

99% quantity of a radioactive substance decays between

If 10% of a radioactive substance decays in every 5 year, then the percentage of the substance that will have decaed in 20 years will be .

If 10% of a radioactive substance decays in every 5 year, then the percentage of the substance that will have decaed in 20 years will be .

If 10% of a radioactive substance decays in every 5 year, then the percentage of the substance that will have decaed in 20 years will be .

The half life of a radioactive substance is 24 hours. Time required for 12.5% of the original radioactive substance W remain is

The half-life of a radioactive substance is 20 minutes. The time taken between 50% decay and 87.5% decay of the substance will be

The half life of a radioactive substance is 20 minutes. The time taken between 50% decay and 87.5% decay of the substance will be

A radioative substance decays 10% in 5 days. The aamount remains after 20 days is [log 3 =0.4771]