The projectile at the top point of the parabolic trajectory explodes into 2 fragments of equal mass. One fragment returns to the starting point of the projectile departure along its previous trajectory. Compare the distance from the starting point to the fall of the second fragment with the range of the projectile, if it had not exploded.

Detailed solution with a brief record of the conditions, formulas and laws used in the decision, the conclusion of the calculation formula and the answer.
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