A car horn has a frequency of 400 Hz. The car is moving away from an intersection at 20 m/s. The frequency heard by a woman standing at the intersection could be:

clinically, some people often have repeated allergies, eczema and respiratory infections or other parts of the infection, in this case, in addition to some routine tests such as tests for white blood cells, immunoglobulin series, lymphocyte subsets, etc., the five immune immunoglobulin tests are also necessary.

answer by yourhope:

answer is

human impact on the environment can be seen in the deterioration of the !

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