Answer: The interest is: " $ 64 .00 " .
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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 ; 
  {Note of interest: 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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