In your body.
the heart
The busiest muscle is probably the tongue or the jaw muscle because if you eat or talk, you use both. But probably the jaw because there are some sounds you can make without the tongue but both are useful.
It's true its the muscle that moves your eyes :)
Busiest what? New York has the busiest stock exchange. Florida has the busiest funeral directors. California has the busiest movie industry.
The only muscle found in the heart is cardiac muscle.
Where is the busiest sreet in Paris
what is the busiest port of Africa
the clavicle muscle is the only muscle found in your heart
The Port of Felixstowe is the busiest port in England, the 6th busiest in Europe and the 35th busiest in the world.
Smooth Muscle
Cardiac muscle.
Cardiac muscle.