\[
\text { a) } \begin{aligned}
P(A \cap B) & =P(A)+P(B)-P(A \wedge B) \\
& =0,3+0,5-0,7=0,1 \\
\text { b) } P\left(A^{c} \cup B^{c}\right) & =P\left((A \cap B)^{c}\right)=\Lambda-P(A \cap B) . \\
& =A-0 \Lambda=0,9 \\
\text { c) } P\left(A^{c} \cap B\right) & =P(B)-P(A \cap B) \\
& =0,5-0,1=0,4
\end{aligned}
\]
b) \( P\left(A^{\varepsilon} \cup G^{c}\right)=P\left((A \cap B)^{c}\right)=1-P(A \cap B) \)
c) \( P\left(A^{c} \cap B\right)=P(B)-P(A \cap B) \)
