(12) Scientists hope that a recent discovery of dinosaur bones in South
America will help them( )the mystery of why the
dinosaurs disappeared.
1 scatter 2 unravel 3 unsettle 4 propel
(13) After a workers' strike forced the company to halt operations,,the management agreed to make some( )and will increase
worker benefits.
1 constrictions2 digressions 3 concessions 4 infractions