Carlos made a diagram to compare two kinds of fish. which label belongs in the area marked Z? a. scales
b. no jaw
c. swim bladder
d. skeleton made of bones

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Which of these statements best describes the st. lawrence seaway? the st. lawrence seaway connects the st. lawrence river with the arctic ocean. the st. lawrence seaway provides an important trading route between the u.s. and mexico. the st. lawrence seaway provides an important trading route for the u.s, but has little value for canada. the st. lawrence seaway connects the great lakes, the st. lawrence river, and the atlantic ocean.

Which of the following was not a major animal on land during the carboniferous period? amphibians insects both a and b none of the above

In general, characteristics that an organism survive and reproduce become more common in a population over time. what mechanism of evolution cause this change?