please explain

3. Given the following Ending Inventory errors: Year 2018 2019 Ending Inventory Error Understated $30 Understated $40 Indicate the error in the following items: 2019 Net Income a) Overstated $70 b) No Error Understated $40 Understated $10 e) Overstated $40 12/31/19 Working Capital Overstated $40 Overstated $10 No Error Understated $40 No Error