Answer:
The correct answer is: 600,000 years
Explanation:
Half-life is the time which is essential or required to decrease a specific substance to half of its initial amount of the substance. So, if a substance has a half-life of 200,000 years then it means it takes 200,000 years to decrease or change into a new substance and remain half of its initial quantity.
half-life amount
0 20000
1 10000
2 5000
3 2500
total half-life = 3 to 2500 atoms of A
so, the time will be = 3 * 200,000 years
= 6000000
Answer: The correct answer is D. Heating by the sun.
Comets are balls composed of dust and ice orbiting around the Sun in elliptical orbits. The orbit of the comet takes it near and far away from the sun. As the comets get closer to the Sun, the heat of the sun vaporizes the materials on the surface of the comet which forms a tail pointing away from the sun.
A comet tail is visible from Earth when they are illuminated by the Sun on approaching the inner Solar System. The solar radiations vaporize the volatile materials of the comet which streams out from the nucleus and carries dust away with it. The pressure due to the Sun’s radiation and solar winds leads to the formation of a tail pointing away from the Sun.
Answer:
14. Carcinogenic
15. Not sure. I believe it is monoclonal antibodies.
