Sound waves can be used to measure ocean depth. this done by sending a sound wave to the floor of the ocean and recording the time it takes to return to a machine. what did the inventory of this machine need to know while developing the machine

as we probably am aware that our atmosphere or air have various levels, each level has different gasses, and each gas has another porousness. at the point when the light originates from lower porousness to higher penetrability, it alters its course. with the goal that implies that when the light originates from the moon to the earth, it alters it's course a lot more occasions. it essentially implies that the state of the light piece of the moon is changed on the earth.

not copied too! hope this !

joke:

h o h o hope you have a merry christmas!

365.25 earth days are in the year of a light year