<h2>APL (<s>15</s> 13)</h2>

    {⎕←⍵⊣⎕DL⍵}&¨⎕

What it does:
    
    ¨⎕       : for each element of the input
    &        : do on a separate thread
    ⎕DL⍵    : wait approx. ⍵ seconds
    ⎕←⍵     : output ⍵