$1.50. Explanation: Desiree earns $120 monthly from her investments. Therefore, her annual investment income amounts to $120 x 12 = $1,440. Additionally, as a band member, she earns $200 weekly, translating to an annual band income of $200 x 52 weeks = $10,400. If her total annual income totals $49,696, her salary income is calculated as $49,696 - ($1,440 + $10,400) = $49,696 - $11,840 = $37,856. This leads to weekly earnings of $37,856 / 52 = $728. Consequently, her hourly rate is determined by $728 / 28 = $26. Desiree aspires to achieve an annual income of $51,880, and assuming her investment and band revenues remain constant, she needs to make $51,880 - $11,840 from her salary, equating to $40,040 annually. Thus, her updated weekly earnings would be $40,040 / 52 = $770 and new hourly earnings of $27.5. Hence, the raise she should request is ($27.5 - $26) = $1.50.