net income: 18,000
>service revenue 56,000 - operating expenses 38,000

cash provided(used) by operating activity: 17,000
solution:
collection of accounts receivable: 42,000*
less - payment of accounts payable: - 25,000**
total cash inflow(outflow): 17,000

*total accounts receivable: 56,000
less: accounts receivable, ending balance: 14,000
total: cash collected from receivables: 42,000

**total accounts payable: 38,000
less:accounts payable,ending balance: 13,000
total: cash payment of accounts payable: 25,000


cash provided(used) by investing activity: (12,000)
solution:
cash outflow from purchase of land: -12,000


cash provided(used) by financing activity: 30,000
solution:
cash inflow from issuance of stock: 30,000