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.
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.
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.
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
it has almost doubled!
Wine today generally has a higher alcohol content compared to in the past, making it stronger.
A footpath over the mountains. The Royal Road was a horse track for mounted official couriers.
They were 5.00 compared to 59.50 today.
About $10,000 today
One major disadvantage of the Babylonian system of mathematics was that it was based on a sexagesimal (base-60) numerical system, which made calculations more cumbersome compared to the decimal system we use today. This system made arithmetic operations more complex and less intuitive for users.
bleak
The most efficient home heating system available on the market today is a geothermal heat pump. It uses the stable temperature of the earth to heat and cool your home, providing significant energy savings compared to traditional heating systems.
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.