Irrigation system gave the ancient civilizations fertile land which helped crops grow. It also allowed for ease of watering which made the process of farming faster.
Answer:
After 6000 years, approximately 500 atoms of carbon-14 will be left in the femur bone of an animal which had 1000 atoms of carbon-14 when the animal died.
Explanation:
The half-life of a radioactive isotope of an element is the time taken for half the atoms present in a given amount of the element to undergo decay or disintegration. For example, the half-life of carbon-14 isotope is 5730 years. This means that, if there are 100 atoms of carbon-14 present in a given sample of a material, in the next 5730 years, approximately, 50 atoms of carbon-14 will be left in the material.
Since the half-life of radioactive isotopes are constant, these radioactive isotopes are used in the determining the ages of ancient life-forms as well as rocks.
In the given example, after 6000 years, approximately 500 atoms of carbon-14 will be left in the femur bone of an animal which had 1000 atoms of carbon-14 when the animal died.
The Answer is
A. Black box,because black absorbs more heat than white
An example is that on a sunny day you were wearing a black t-shirt you would be sweating you bottom off but if you were wearing a white t-shirt you would be less hot and not sweating your bottom off. Why? Because black absorbs more heat rays than white does
D. flammability
is a chemical property
