For two events $A , B$,
$$\mathrm { P } \left( A ^ { C } \cup B ^ { C } \right) = \frac { 4 } { 5 } , \quad \mathrm { P } \left( A \cap B ^ { C } \right) = \frac { 1 } { 4 }$$
what is the value of $\mathrm { P } \left( A ^ { C } \right)$? (Here, $A ^ { C }$ is the complement of $A$.) [3 points]\\
(1) $\frac { 1 } { 2 }$\\
(2) $\frac { 11 } { 20 }$\\
(3) $\frac { 3 } { 5 }$\\
(4) $\frac { 13 } { 20 }$\\
(5) $\frac { 7 } { 10 }$