If you are talking about frequency in terms of waves, it is in seconds^-1
 
        
                    
             
        
        
        
Answer:
Autumnal equinox right ascension = 12 hours; declination = 0°; Sun rises at 90° azimuth and sets at 270° azimuth. December solstice right ascension = 18 hours; declination = -23.5° Sun rises at greater than 90° azimuth and sets at less than 270° azimuth.
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A vaccine works by training the immune system to recognize and combat pathogens, either viruses or bacteria.
        
                    
             
        
        
        
Answer: A,B and C
Explanation
        
             
        
        
        
Answer:
A. would be the correct answer