A. A concave lens is used to correct vision
Tantalum.................
Answer:
A. Plants will only flower during long day periods when the day length exceeds their necessary photoperiod
Explanation:
Photoperiodism is a phenomenon that refers to the response of an organism to the length of day. This phenomenon causes a physiological change in the organisms involved (plants or animals). However, the best studied example of change caused by photoperiodism is that of FLOWERING IN PLANTS.
Different plants flower at different times in response to the day length. Certain plants called LONG DAY PLANTS e.g. spinach and potato etc only flower when the length of day exceeds their photoperiod (threshold), which is usually 12 hours. These plants require very short periods of darkness to flower.
Hence, according to the question, FLOWERING response in plants is the best explanation to describe photoperiodism.
Answer: it works better when closer to the energy source
Explanation:
I just know
Carbon skeletons may vary in length, shape, number and location of double bonds and other elements covalently bonded to available sites.
A carbon atom contains four valence electrons thus, exhibiting a strong tendency to make covalent bonds with other atoms so as to complete its octet. Covalent bonds join carbon atoms together in long chains that create the skeletal framework for organic molecules.
A carbon atom could be linked to as many as four additional carbon atoms in an organic compound. Carbon atoms can also quickly form double bonds (where four electrons are shared among two atoms) and triple bonds (where six electrons are shared).
This variation in carbon skeletons contributes to the diversity and complexity of organic molecules.
To learn more about covalent bonds here
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