Answer
$\$ 11877.5$.
This means that the total income for one month is $\$ 11877.5$.
Work Step by Step
The dot product of $u \cdot v$ is
$$u \cdot v=3140 \times 2.25+2750 \times 1.75=7065+4812.5=\$ 11877.5$$
This means that the total income for one month is $\$ 11877.5$.