A $6\mathrm{.}5F$ capacitor is charged by a $135$ V battery $($see the figure $($Figure $1)$ a$)$ and then is disconnected from the battery. When this capacitor $(C_1)$ is then connected $($see the figure b$)$ to a second $($initially uncharged$)$ capacitor, $C_2,$ the final voltage on each capacitor is $25$ V $.$

Figure

$1$ of $1$

Part A

What is the value of $C_2?[$Hint: Charge is conserved.$]$

Express your answer using two significant figures.