Answer:
Closed the first one
Explanation:
In amphibians, reptiles, birds, and mammals, blood flow is directed in two circuits: one through the lungs and back to the heart, which is called pulmonary circulation, and the other throughout the rest of the body and its organs including the brain (systemic circulation).
most mammals, have closed cardiovascular systems. The two main circulation pathways in invertebrates are the single and double circulation pathways.
Not really sure but I think is that rodents mate randomly but wait for someone else to answer cause I’m not 100% sure
Answer:
The earliest known life-forms on Earth are putative fossilized microorganisms, found in hydrothermal vent precipitates, that may have lived as early as 4.28 billion years ago, relatively soon after the oceans formed 4.41 billion years ago, and not long after the formation of the Earth 4.54 billion years ago.
Explanation:
I don’t know but maybe they are maybe they’re not
Answer:
It is not a reliable test because the people's answer may be biased by prior familiarity with the brands they are testing.
Explanation:
The results are most likely unreliable because if the people who are testing the two brands of lemonades (brand X and Y) know the two brands already from before the test, their responses may be biased according to what they believe <em>a priori</em> that is better. In other words, they could simply choose their favorite brand without objectively analyzing the taste.