What can scientists learn from the rate at which radioactive elements decay?
A. a rock's absolute age*
B. the relative age of rock layers
C. where one soil horizon ends and the next begins
D. the difference between molds and casts.
After six half-lives, what percentage of a radioactive sample will remain?
A. 0%-1%
B. 1%-3%*
C. 3%-6%
D. 6%-10%
Earth's oceans, atmosphere, and continents began to form during the first several hundred years of Precambrian time.
A. True*
B. False
A mold forms when minerals replace all or part of an organism.
A. True
B. False*
1,2, & 4 are correct. I could not obtain information on #3.
#3 is True i think.
All four are correct
What can scientists learn from the rate at which radioactive elements decay? The rate at which radioactive elements decay can provide information about the absolute age of rocks. By measuring the amount of remaining radioactive isotopes and knowing their half-life, scientists can calculate the time that has passed since the rock formed.
After six half-lives, what percentage of a radioactive sample will remain? To determine the percentage of a radioactive sample that remains after a certain number of half-lives, you can use the formula: Remaining Percentage = (1/2)^(number of half-lives) * 100. In this case, since it's six half-lives, the formula would be: Remaining Percentage = (1/2)^6 * 100 = 1.5625%. Therefore, option B is correct - after six half-lives, approximately 1%-3% of the radioactive sample will remain.
Is it true or false that Earth's oceans, atmosphere, and continents began to form during the first several hundred years of Precambrian time? The statement is False. Earth's oceans, atmosphere, and continents took much longer than several hundred years to form. These processes occurred over billions of years during the Precambrian time.
Is it true or false that a mold forms when minerals replace all or part of an organism? The statement is False. A mold is an imprint or cavity left in a rock or sediment when an organism decays or dissolves. It does not involve minerals replacing the organism.