Answer and Explanation:
The operating activities is
Cash collections from customers $300,000
Less:
Cash payments to suppliers $95,000
Interest paid on debt  $25,000
Cash provided by operating activities $180,000
a. The net cash provided or used by investing activities
Sales of old equipment $72,000
Less:
Purchase of bus $33,000
Cash provided by investing activities $39,000
b. The net cash provided or used by financing activities is
Cash dividend $ 80,000
Repurchase of stock $ 55,000
Cash used by financing activities -$135,000
d. The net increase or decrease in cash is
= $180,000 + $39,000 - $35,000
= $84,000