Una esfera de 4 kg se desplaza a una velocidad determinada y choca con otra masa es de 2 kg que se desplaza a una velocidad de 7 m / s, si se produce el choque la primera esfera se desplaza con una velocidad de 12 m / sy la segunda se desplaza con una velocidad de 5m / s ¿Cuál era la velocidad de la primera esfera antes del choque?

What is the answer for this. the correct answer only

In physics the desire of an object to keep doing what it is doing is termed?

In which situation has the independent variable for the experiment been changed? check all that apply. changed from counting the number of duckweed at day 0 and day 14 to counting them every day changed from testing duckweed growth in beakers to testing duckweed growth in large outdoor tanks changed from testing the effect of ph on duckweed growth to testing the effect of light levels on duckweed growth changed from testing the effect of acid ph on duckweed growth to testing the effect of basic ph on duckweed growth