Answer: 1. L1 produces strings with even number of bs and bs always occur in consecutive pairs. When L2 is concatenated, the number of bs generated can be odd . So now all strings can be generated from this. So (a,b)*. Solution Answer: 1. L1 produces strings with even number of bs and bs always occur in consecutive pairs. When L2 is concatenated, the number of bs generated can be odd . So now all strings can be generated from this. So (a,b)*..