Answer:
scientific theory is the answer
IT IS NOT POSSIBLE to produce malleable cast iron in pieces having large cross sectional dimension. This is because, iron has a very rapid cooling rate and it will not be possible to achieve this rate at different cross sectional areas in a sheet of iron.
Answer: etiolation of plant growth in shade, with fast growing cell without chloroplasts. Out of shade, cell differentiate again to produce photosynthesising cells
Explanation: It is a subjective decision as to what is ‘best’. Good examples are plant responses to changes in the nutrient supply.
when soil nitrogen is depleted some plants, such as legumes, grow nodules on their roots, with cells that release chemical signals to attract nitogen fixing bacteria.
Lack of light induces etiolation in many plants. New cells elongate and develop without chloroplasts, with rapid cell division exhibiting gravitropism, extending upward. When they grow beyond the shade area, cell differentiation changes again, to produce photosynthesising cells.