Two small metal cubes with masses $2\mathrm{.}0$ g and $4\mathrm{.}0$ g are tied together by a $4\mathrm{.}9-$cm$-$long massless string and are at rest on a frictionless surface. Each is charged to $+2\mathrm{.}5$ C$.$

What is the energy of this system?

Express your answer in joules.

What is the tension in the string?

Express your answer with the appropriate units.

The string is cut. What is the speed of $2-$g

$-$cube when the cubes are far apart?

Hint: There are two conserved quantities. Make use of both.

The string is cut. What is the speed of the $4-$g

$-$cube when the cubes are far apart?

Hint: There are two conserved quantities. Make use of both.