The three Invaders return to their home prefecture of Hokkaido for a required summer school day. On the bus ride to school, Mone starts talking about Hokkaido's seven folk legends while Chihori shares random facts about space. As Yuina responds to the girls' wacky conversation with her usual comical comebacks, she is overcome with a very strange feeling about the situation.
That's the speed of sound!
!تلك سرعة الصوت
Also in Schallgeschwindigkeit.
A la velocidad de la luz.
A la velocidad de la luz.
Une vitesse supersonique.
Andava alla velocità del suono!
Isso é a velocidade do som!
Это скорость звука.