
Since the sound travels from the submarine to the object AND back, it actually travelled 3625x2=7250m.

Speed of sound: 1450m/s
Answer:
<em>If the Universe holds enough matter, including dark matter, the combined gravitational attraction of everything will gradually halt this expansion and precipitate the ultimate collapse. Over time, galaxies, then individual stars, will smash into each other more frequently, killing off any life on nearby planets.</em>
Answer:
option b
Explanation:
There is an object pulled inward in an electric field.
We have to find out of the four options given which is true.
a) The object has a neutral charge is false since when electric field pulls the object inward, there is a charge inside.
b) The object has a charge opposite that of the field, this option is correct since there will be an equal and opposite charge created by the object
c) The object has a negative charge will be correct only if the original charge was positive hence wrong
d) The object has a charge the same as that of the field is incorrect since this would be opposite the charge
So only option b is right