Answer:
In the 1960s, scientists found evidence that new material is indeed erupting along mid-ocean ridges. The scientists dived to the ocean floor in Alvin, a small submarine built to withstand the crushing pressures four kilometers down in the ocean. In a ridge’s central valley, Alvin’s crew found strange rocks shaped like pillows or like toothpaste squeezed from a tube. Such rocks form only when molten material hardens quickly after erupting under water. These rocks showed that molten material has erupted again and again along the mid-ocean ridge.
When scientists studied patterns in the rocks of the ocean floor, they found more support for sea-floor spreading. You read earlier that Earth behaves like a giant magnet, with a north pole and a south pole. Surprisingly, Earth’s magnetic poles have reversed themselves many times during Earth’s history. The last reversal happened 780,000 years ago. If the magnetic poles suddenly reversed themselves today, you would find that your compass needle points south.
Explanation:
I found this somewhere.
<span> Basically the male will have CC, the hen will have cc, and neither of them will have I. The key thing is that _all_ the chicks are coloured.
The male must have at least 1 C to be coloured, and cannot possess the dominant I. The hen has cc and/or an I to not be coloured.
That one chick is coloured would tell you little - only that the hen couldn't have 2 inhibitor alleles because otherwise the chick would have to have one and it doesn't.
However, for all of many chicks to be coloured, that means that the hen can't have any inhibitor alleles (otherwise around 50% would be white for that reason alone).
So to be colourless, the hen must be cc. However, if the male had only 1 colour allele (ie it was Cc) that would still mean that 50% of the chicks would be Cc (daddy's 'c' and one of mummy's 'c's).
Hope this helps please award brainly :)
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A. They impede fish migration and spawning
