Essentially all of it, for your life is short compared with the half-life of C-14 at 5700 years.
But that concept has to be modified to allow for the exchange of tissue material in your lifetime.
And when you were born you weighed only a few kilograms, whilst today you weigh several tens of times that - of which some will be C-14. So the answer is difficult and uncertain and uninformative.
the Henry system
Yes. Originally, bumpers were merely designed to protect the vehicle from damage. Today, bumpers are designed as part of the shock absorbing system of a car.
The nervous system of the body is currently not transplantable. Damaged nerves can be grafted in the hope that they will grow back together, but this is not 100% reliable and no section of the central nervous system can be replaced once lost.
Hipparchus is the man credited with developing the global grid system made up of imaginary lines of latitude and longitude. Though he was born in 190 BC and died in 120 BC, his grid system is still used today.
English system The name for the current system of naming organisms in latin (e.g. Homo sapiens) is called Linnaean Nomenclature. It is made up of eight different taxonomic ranks, so the full name of any organism in this system would generally be eight words.
more reliant on the patronage system to select employees
MHZ Megahertz
compared to today, the world used to have 50% more forests compared to today, the world used to have 50% more forests
They were 5.00 compared to 59.50 today.
A footpath over the mountains. The Royal Road was a horse track for mounted official couriers.
About $10,000 today
it has almost doubled!
bleak
the world only used half of the amount we use today in the past because of global water wasting and pollution
micro computers can occupy physically a small amount of space compared to main frame and mini computer, as we all know for today that super computers are the most fastest high performance system and also has a largest memory.
there is still the same amount of water on earth as their was 100 years ago or in fact 1 million years ago. The fact is that today less water is in ice form then there was 100 years ago.
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