Answer:A-wave X is transverse and wave Y is longitudinal 
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46 chromosomes. Each consisting of one chromatid
        
             
        
        
        
Answer:
generally considered to have originated in the late nineteenth century as a reaction to the abuses of big business and the problems that plagued the lower socio-economic classes of that era. 
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The right answer is HEPA filter.
A HEPA filter (High Efficiency on Particles Air) can filter up to 99.97% of 0.3μ aerial particles.
These filters are used to clean the air and retain suspended particles (dust, pollen, bacteria etc.) and other particles that can cause respiratory allergy in sensitive subjects.
They are very used in sterile rooms