Question

" having muscles of iron & nerves of steel" means​

Answer 1

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The principle of reversibility presupposes that the attenuation of a light ray during its passage through an optical medium because of reflection, refraction, and absorption is not affected by a reversal of the direction of the ray.

Answer 2

Explanation:

What we want is muscles of iron and nerves of steel. We have wept long enough. No more weeping, but stand on your feet and be men.

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