A) a well preserved piece of wood found at an archaeological site has 43 % of the carbon-14 that it must have had when it was living. using the fact that carbon-14 has a half-life of 5700 years, calculate the age (in years) of this piece of wood.

b) a different piece of wood is found to have 9 % of the carbon-14 that it must have had when it was living. calculate its age (in years) and enter it in the box below.