On July $2,$ the billing date, Marvin Zug had a balance due of $$194\mathrm{.}25$ on his credit card. His card charges an interest rate of $1\mathrm{.}25\%$ per month. The transactions he made are to the right.

a$)$ Find the finance charge on August $2,$ using the previous balance method.

b$)$ Find the new balance on August $2.$

Marvin made the following transactions during the month.

$\backslash$table$[[$July $7,\backslash$table$[[$Charge:$],[$Office supplies$]],$$$60\mathrm{.}52$