A guitar is perfectly tuned. You tighten the strings. Which of the following is true

A. The wavelengths of the waves are longer than before
B. The speed of the sounds coming from the guitar is faster
C. The amplitudes of the sounds are larger the frequencies of the sounds fom the quitar are higher

Which of the following correctly describes what happens when an atomic bomb explodes? small pieces of fissionable material are joined and form a body with a mass greater than the critical mass, the relative number of neutrons escaping decreases, and a chain reaction and explosion result. large pieces of fissionable matter are brought together quickly and form a body with a mass smaller than the critical mass, the relative number of escaping neutrons increases, and a chain reaction and explosion result.