Answer:  The interest is:  " $ 64 .00 " .
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Step-by-step explanation:
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Take note of the formula:
" Ⅰ = Prt " ; 
 → that is:
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 →   " Ⅰ = P * r * t " ; 
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In which:  
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  " Ⅰ = the interest " ; 
  " P = the Principal amount of money " ; 
  " r = rate " (expressed as the "decimal form" of the percentage) ; 
  " t = time " (in years) ; 
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We are given:  
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  P = $400 ; 
  r = 0.08 ;  
  {<u>Note of interest</u>:  That is " 8% " ; since "8 % "  = "(8/100)" ; 
                                                                           = "(8 ÷ 100)" 
                                                                           = " 0.08 ".}.
  t = 2 ; {that would represent:  " 2 (two) years".}.
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We are to solve for "Ⅰ" ; the amount of "Ⅰnterest" :
→ To solve for "Ⅰ " ; we plug in our given values; and calculate:
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   →  Ⅰ = P * r * t ; 
         = 400 * 0.08 * 2 ; 
         =  64 .
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   →  Ⅰ = $ 64.00 .
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Hope this is helpful to you!
 Best wishes!
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