Within a vacuum, the property to all electromagnetic waves is their what?

Two particles of masses m and 2m are placed on a smooth horizontal table. a string, which joins these two masses, hangs over the edge supporting a pulley, which suspends a particle of mass 3m. the pulley has negligible mass. the two parts of the string on the table are parallel and perpendicular to the edge of the table. the hanging parts of the string are vertical. find the acceleration of the particle of mass 3m.

Iwill give brainliest if you answer right : )

A17,250 kg rocket is pushed with a thrust of 6,450,284 n. what is the acceleration of the rocket?