Explain the theory of relativity pl I know basically what it is, but its just sooo confusin :

In positive numbers less than 1, the zeros between the decimal point and non zero are significant

Física: un futbolista patea hacia el arco con una velocidad de 15m/ah, calcular: a)el alcance para un ángulo de tiro de 25º, b) el tiempo que el balón permanece en el aire.

What is the kinetic energy of a baseball moving at a speed of 40 m/s if the baseball has mass of 0.15 kg?