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Answer:
[tex]\frac{20r^5}{c}[/tex]
Step-by-step explanation:
[tex]4c^{4}[/tex]·[tex]5c^{-5} r^{5}[/tex]
=[tex]4c^{4}[/tex]·[tex]\frac{5 r^{5}}{c^{5} }[/tex]
=[tex]\frac{20c^{4}r^{5} }{c^5}[/tex]
=[tex]\frac{c^4}{c^4} \frac{20r^5}{c}[/tex]
=[tex]\frac{20r^5}{c}[/tex] or =[tex]20c^{-1}r^5[/tex]