Answer:
The problems that can be caused by Expansion or Contraction a;long with the solutions are:
Explanation:
- The railway tracks made of steel expand during the summer and contract during the winter. This can cause them to become curved during the summer thereby causing rail derailment.In order to prevent this, an air gap is kept in between the railway lines so that they get the space to expand without getting curved.
- The electric wires linking the telegraph posts are made up of metals and so they expand in the summer and contract in the winter, which can cause them to tear. This is why the wires are loosely fixed so that they can expand and sag in the summer and contract and tighten in the winter.
- Bridges are constructed with joints where some space is maintained to allow the easy expansion and contraction in summer and winter respectively.
If your asking how kitchen tools avoid rusting the answer is to maintain them dry after use or buying stainless steel that contains chromium which helps the metal protect it from rusting
I, seems to be the answer, because its not a sexual reproduction, (this occurs in cells, its not sexual reproduction, you would need the egg and sperm.
A polygenic trait is a trait controlled by many (poly) genes. Human skin color is an example; it thought to be the controlled by about 12 genes.
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