GMC 2000 Safari Owner's Manual page 56

CAUTION:
Never hold a baby in your arms while riding in a
--
vehicle. A baby doesn't weigh much until a
crash. During a crash a baby will become so
heavy you can't hold it. For example, in a crash
-
at only 25 mph (40 km/h), a 12 lb. (5.5 kg) baby
-
will suddenly become a 240 lb. (110 kg) force on
your arms. The baby would be almost impossible
to hold.
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