$4$ capacitors are in a circuit. A combination of $3$ capacitors each with a capacitance of $2\mathrm{.}5$ F are in parallel with each other, and this combination is in series with a $3\mathrm{.}0$ F capacitor.$$

$(1)$ Calculate the equivalent capacitance in the circuit. 

 

 $2)$ Determine the energy storage in the circuit if the potential difference is $160$V .