Polly Is a Cash Basis Taxpayer with the Following Transactions

Polly is a cash basis taxpayer with the following transactions during the year: $\begin{array}{llcc} \text { Cash received from sales of products } &\$90,000 \\ \text {Cash paid for expenses (except rent and interest) } &\$30,000\\ \text {Rent paid on a leased building for 24 months beginning December 1 } &\$54,000\\ \text {Prepaid interest on abank loan, paid on December 1 , for the next 3 months } &\$6,000\\ \text {Four months' rent received on a leased building, on October 1 } &\$8,000\\\end{array}$
Calculate Polly's income from her business for this calendar year.