How does earths magnetic field provide evidence for seafloor spreading

Magnetic reversal proves seafloor spreading because we can see the polarity of the Earth's magnetic field in rocks. As magma cools, particles in it get “frozen” in the direction of the magnetic field. ... The magnetic evidence shows that the oldest rocks are far away from the ridge and the newest rocks are closest.

the diploid number of chromosomes is sometimes represented by the symbol 2n. for the fruit fly, the diploid number is 8, which can be written as 2n = 8, where n represents twice the number of chromosomes in a sperm or egg cell.

just finished the test, the answer is d, greg is the least cost-effective because he charges the most for the project