please solvethe relative density of wood is 0.64 what is the density in the SI system and the CGS system ​

How much force must a locomotive exert on a 12840-kg boxcar to make it accelerate forward at 0.490 m/s2?

Astronomers discover an exoplanet (a planet of a star other than the sun) that has an orbital period of 3.87 earth years in its circular orbit around its sun, which is a star with a measured mass of 3.59 x 1030 kg. find the radius of the exoplanet's orbit.

An isotope undergoes radioactive decay by emitting radiation that has a –1 charge. what other characteristic does the radiation have?