1. which is the longest wall in the world?

The Great Wall of China is the longest wall in the world.

1. c- the tunnel project was worthwhile.

2. b- to inform about the value of the tunnel project

recent brain research has shown some surprising benefits as a result of formal musical training. learning to play a musical instrument appears to develop parts of the brain that can even influence academic results. the studies indicate that the earlier a child begins training, the more benefits there are. one such study showed that children who began musical studies before the age of seven had a more developed brain in the region where language production and auditory processing take place. scientists believe there is mounting evidence to show that early musical training can improve brain function.

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