The correct answers are:
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  1)    " 0.8  =  80 % "  .
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  2)    "  =  62. 5 % " .
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  3)   " 0.01  =  1 % " .
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Explanation:
To solve:
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Write the numbers: Â " 0.8 " ; Â " 5/8 " ; Â and: Â " 0.01 " ; Â as "percentages" .
To write a "number" as a "percentage" :
You take the "number" ; Multiply that "number"  by "100"  ;  AND: add a  "percent symbol";
         →  that is:  " % " ;
         → to denote the "percentage" ;  or, "parts per hundred" .
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Let us start with the number: Â " 0.8 " .
→  " 0.8 "  *  100  =  ?
→  Take the decimal point, and move it 2 decimal spaces to the right; since we are "multiplying" by "100" (which has "2 zeros")  ;
→   0.8  * 100 = ?  ;  If we move the decimal space "one space" forward, we have:  "8" .  If we move the decimal space yet "one more space forward" ;
   →  "8."  to:  " 80 " .
→ Then we add the "percent symbol":
   →  " 80 "  ;  to:  " 80 % "
 " 0.8  =  80 % " .
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Other method:
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→ Note that "percentage" means:  "parts per hundred" :
→ Given:  " 0.8 " ;  Convert to a "percentage" :
→  " 0.8  = " ;
    →  " " ;
    →  Find the "?" value.
    →  To do so; look at the "denominators" :
         →  " 10 * (what) = 100 " ?
         →  Divide each side by "10" ;
         → " [10 * what ] / 10  = 100 / 10 " ;
         →  to get: Â
         →  " [what] " =  "10" .    Â
         →   So;  " " ;
         →   If  "{10 * 10 = 100}" ;  then, "{8 * 10 = 80}" .
         →   So;  " {?} " =  " 80 " .
         →   So;   " " ;
         →   As such:  " 0.8 "   =  " () " ;
                            =  " 80 "  parts per hundred  ;
                            =  " 80  % " .
" 0.8 " Â = Â 80 % Â " Â . Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
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Now, let convert: Â "()" ; into a percentage.
→  Multiply by "100" ;
→  "()"  *  100  ;
→   "()   *  ()"  ;
→   "()"  ;
→  "()"  ;
  =   " { 500 ÷ 8 } "  ;
 =  " 62. 5 "  ;
→  Now, add the "percent symbol" ;
  →   "  62. 5 "  ;   →  62. 5 % " .
 "  =  62. 5 % " .
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Now, let us finish with our last "given value":
Convert: Â " 0.01 " ; Â to a "percentage" :
→  " 0.01 "  *  100  =  ?
→  Take the decimal point, and move it 2 decimal spaces to the right; since we are "multiplying" by "100" (which has "2 zeros")  ;
→   0.01  * 100 = ?  ;  If we move the decimal space "2 spaces forward" , we have:  " 1 " . Â
As such:
   →  " 0.01 "  to:  " 1 " .
→ Then we add the "percent symbol":
   →  " 1 "  ;  to:  " 1 % "  .
 " 0.01  =  1 % " .
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Hope this answer is of help to you.
Best wishes!
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