Go over materials that where gaven to you and maybe ask your teachers about the subject on the test but just come prepared and be ready for all that you learn about
Answer: The model is depicting the glacier erosion.
Explanation:
The glaciers are responsible for causing erosion of the earth. They transport the materials away from the locations were they are earlier situated. They carve the materials present beneath the land. They erode the materials like soil, pebbles, boulders, against the pressure of the unstable mass of the ice moving down the slope. The broken ice mass carriers away the broken rocks, materials and soil debris far away from the places where they have been originally situated. This causes the glacial erosion. Also the broken and displaced rocks displace the soil and other materials come in contact with during erosion.
According to the given situation, the ice formed with water only had no impact on the tinfoil on the other hand the ice containing the sand and rocks removed the tinfoil from places. This is because of the friction created by the sand and rocks on the tinfoil. The glacier material like ice, soil, rocks due to friction erode the material come in contact with it with an appreciable pressure underneath.
In order for offspring to have a dominant mutation, they need at least one copy of the allele from either or both parents. So yes, at least one of the parents must have the mutated gene in order for the offspring to have the mutation.
For your second question, I'm not quite sure what you mean so I will restate two possibilities for what I think you mean:
1. The offspring does not have the mutation if none of the parents have the mutated gene: this is correct.
2. If the mutation is recessive and the child has only one copy of the mutated allele, then the child will not show the mutation. If none of the parents had the mutated gene, then it would not be possible for the child to have the mutated gene or show it.
Long term is to mate. I don't know about short term