A child is sliding down a hill on a sled .
It is impossible that a child is attempting to jump a ramp on a sled at the bottom of the hill .
It is impossible that a child is attempting to jump a ramp on a sled at the bottom of the hill .
It is probable that a child is attempting to jump a ramp on a sled at the bottom of the hill .
A child is attempting to jump a ramp on a sled at the bottom of the hill .