Answer:
Placer mining can be less damaging to the environment than surface mines, as the sediment is returned to the water after the minerals have been extracted.
Explanation:
In experiments with phosphorus and sulfur, both of which burned readily, Lavoisier showed that they gained weight by combining with air. With lead calx, he was able to capture a large amount of air that was liberated when the calx was heated. To a suspicious Lavoisier, these results were not explained by phlogiston
Answer:
A closed circuit doesn't allow the flow of electrons. an open circuit does. example: if you turn off a switch in your house. you 'broke the circuit it is closed.
Answer:
C
Explanation:
The brother has different alleles for the blood type gene than his sister does. Blood type is inherited from parents like many other traits that can be displayed on a punnet square. Depending on what the parents blood type alleles were, the brother and sister could have different blood types.
A different number of chromosomes doesn't lead to different blood types, so D is wrong. And A is incorrect because the number genes also does not affect blood type. And I think the blood type genes are on the same chromosome, so B is wrong. C is correct because blood type is inherited by alleles, and different alleles can cause different traits, such as blood types.
