Respuesta :

Answer:
mass = 50

Work:
e=1/2mv^2 [substitute in]
2500 = 1/2m(10)^2 [simplify]
2500 = 1/2m100 [divide both by 100]
25 = 1/2m [divide both by 1/2]
50 = m

Now you can mark her brainliest