1.) A student has attached a 0.25 kg stone at the end of a cord and rotated it in the horizontal circle with a radius of 3 m. What will be the centripetal force of the object if the final speed of the stone is 4.5 m/s?

2.) What is the mass of an object accelerating 7 m/s2 in a circular path with a force of acceleration equal to 420 N

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