MC prob...in a game..help needed.please

hi every 1 …

i hav a small prob…regarding movieclip …im doing a flashMX car game … where ,when the obstacles hit the car …the obstacles disappear…the prob here is …the obstacles disappears only when it passes by the center point of the car(which is a MC)…So i need a code to consider the whole car(MC) as a single object so that whenever any obstacles touches any part of the car, it disappears… CAN ANY 1 PLeASE HELP ME…

ill be very thnk full…

thank you in advance …
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