57.0 is it rounded to three sig figs. You count three spaces then round from there, which would be the zero and you would round down because the four is there.
B. Two significant figures
Your final answer can only have as many significant figures as the number that has the least amount of significant figures in it, which is (0.0065)
Answer:
Those with 3 protons and 3 neutrons are known as the isotope lithium-6. Those with 3 protons and 4 neutrons are known as the isotope lithium-7.
Explanation:
Answer:
56
Explanation:
The mass number of an atom is a sum of its number of protons and neutrons. Iron (Fe) has an atomic number of 26. This means that it has 26 protons. Since we know it has 26 protons and are told it has 30 neutrons. The mass number of this atom of Iron is 26+30 = 56
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Answer:
Carbon dioxide levels in the Earth's atmosphere have been steadily increasing.
Carbon has a longer average lifetime in the atmosphere.
Explanation:
Today the level of carbon dioxide is higher than at any time in human history. Scientists widely agree that Earth’s average surface temperature has already increased by about 2 F (1 C) since the 1880s, and that human-caused increases in carbon dioxide and other heat-trapping gases are extremely likely to be responsible.
The lifetime in the air of CO2, the most significant man-made greenhouse gas, is probably the most difficult to determine, because there are several processes that remove carbon dioxide from the atmosphere. Between 65% and 80% of CO2 released into the air dissolves into the ocean over a period of 20–200 years.