A46000-$kg$ railroad freight car collides with a stationary caboose car. they couple together, and 16 percent of the initial kinetic energy is dissipated as heat, sound, vibrations, and so on. what is the mass of the caboose?

Im not from america so could you explain what route 70 is? how much km or miles does it have? am i supposed to know ,from this text,what the s(road) is? how many km or miles it has?

Blue light reflected from the ball enters human eyes.

Two 10¢  coins  (dimes)  carrying identical charges  are  lying 2.5 m apart  on a  table.  if each  of  these coins experiences  an  electrostatic force  of  magnitude 2.0 n due  to the  other coin.  the charge on each coin is :     52.2 uc