Answer:
<u><em>Race</em></u> refers to the highly influential but mistaken identity that one or more genetic traits can be used to identify distinctive and exclusive categories of people.
Explanation:
Race refers to the discrimination of individuals depending on distinctive features such as colour etc.
The discrimination on the basis of race was very common in the past ans still be observed today in many tribes, places and countries. For example, the discrimination of the african- american race from the white americans was common in the past ans is even common today.
True. Sodium is more reactive than magnesium.
I think the answer should be the second one
Using the Doppler shift effect
If the celestial body is in the blue shift, then its moving towards earth and if it's in the red-shift then it's moving away from earth.
Explanation:
Doppler shift effect is a phenomenon that occurs in waves due to relativity. When an object is relatively moving toward an observer, it tends to ‘compress’ the waves into a higher frequency/ shorter wavelength. Visible light will be observed in blue shift because blue light is of higher frequency than red. If the object is relatively moving away from the observer, it tends to ‘stretch’ the waves. Remember ALWAYS this is relative to the observer. hence giving them the perception of viewing the object in longer wavelength. The object is observed in red shift because red light it has a longer wavelength/lower frequency than blue light.
This phenomenon is not limited to light waves, but happens even in mechanical waves like sound. When a wailing ambulance is approaching you, you hear it in high pitch. However, when it passes you and moves away from you, you hear it in low pitch.
Learn More:
For more on Doppler shift effect;
brainly.com/question/6787528
brainly.com/question/3841958
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