A radar signal is sent into space and travels at a speed of 300,000 km/s. It takes 20 seconds for the signal to return to Earth. What is the velocity of the radar signal?

Group of answer choices

20 s

300,000 km/s

300

1

answerspecific gravity;

b.false that your answer

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.