Answer: 4282.928 = 4283 years
Explanation:
Data given;
Carbon 14 half life = 5740
No (initial radiation) = 0.230 Bq/g
Nf (final radiation) = 0.137 Bq/g
First we find the decimal fraction of the remaining half life of the carbon 14
k = No / Nf
k = (0.137 / 0.230) = 0.595652
So to find how many half-life has elapsed, we say
(1/2)^n = k
(1/2) ^n = 0.595652
Therefore
n log 0.5 = log 0.595652
n = ( log 0.595652) / ( log 0.5)
n = 0.747457
To get the elapsed time or how old the sample is;
We say
Carbon 14 half-life × n
5730 yrs × 0.747457
= 4282.928
= 4283 years.
So the sample of the wood is 4283 years old.
The nurse may say something along the lines of "The order will be submitted to your physician. Your parents will not know." It is only a simple test to see whether the boy has contracted the Human Immuno-Deficiency virus, and thus is not anything that requires interference on the parents' part, which may bring embarrassment on the adolescent. The nurse is practicing general ethics and her moral code here.
If a person falls asleep while talking, riding a bike, standing or while doing physical activities, it should not be taken casually. It is a sign of a severe sleep disorder.
Narcolepsy is a neurological condition where the brain's ability to control the sleep-wake cycle is disrupted. In such case the patient can fall into Rem sleep after falling asleep for 90 minutes.
Nolan's behavior indicates that he is suffering from Narcolepsy and must consult a sleep clinic.
The gametophyte of a liverwort produces sperm in a structure called <span>antheridium.
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An antheridium<span> or antherida (plural: </span>antheridia<span>) is a </span>haploid<span> structure or organ producing and containing male </span>gametes<span> which is called </span>antherozoids<span> or </span>sperm<span>.</span>
