Answer:
hope it helps you...
Explanation:
acid rain is harmful for crop,and soil.
Answer:
See the answer below
Explanation:
There are several scientists that contributed to the understanding of the cell. Some of them and their contributions are as follows:
Anton van Leeuwenhoek: He invented the first primitive microscope and was able to view some unicellular microscopic cells such as protozoans and bacteria. He disproved the theory of spontaneous generation by his discoveries.
Robert Hooke (1665): He improved further on the microscope invented by Leeuwenhoek and was able to view compartment-like rooms when tissues of cork were sectioned. He tagged the compartment as 'cell'.
Schleiden (1804–1881): Using an improved microscope, he was able to extensively study plant tissues and borrowed the word coined by Hooke (cell) to describe the component of the plant tissues.
Theodor Schwann (1810–1882): He studied animal tissues and made a similar observation as Schleiden.
Through their various studies, Schleiden, Schwann, and another scientist, Rudolf Virchow later developed what is nowadays known as the cell theory
Answer:
<u>2 years</u> to decay to a mass of 50g.
Explanation:
given:
100g of substance with a half life of 2 years
to a mass of 50g
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
ln 2 0.693
Half life T1/2 = ---------- = -----------
λ λ
where λ = rate constant
The initial amount of 100 grams is decaying to a mass of 50 grams is half of its initial value.
Therefore, it will take 2 years for the decay.