Answer Happy

PLEASE HELP!!! I am totally confused for this percentage!
How do I calculate the % error? Ideal gas law....R=0.0821 (The first row is the initial volume and moles)
V, mL 40 mL 65 mL 60 mL 55 mL 50 mL 45 mL 40 mL 35 mL 30 mL 25 mL 20 mL T,C 0.0018 mol 22.2 °C 22.2 °C 22.2 °C 22.2 °C 22.3 °C 22.3 °C 22.3 °C 22.4 °C 22.4 °C 22.2 °C % Error (=) P, hPa (-)850 hPa (-)850 hPa (-)850 hPa (-)825 hPa (-)800 hPa (-)800 hPa (-)775 hPa (-)725 hPa (-)650 hPa (-)575 hPa ?????? V, L 0.065 L 0.060 L 0.055 L 0.050 L 0.045 L 0.040 L 0.035 L 0.030 L 0.025 L 0.020 L T, K 295.7 K 295.7 K 295.7 K 295.7 K 295.8 K 295.8 K 295.8 K 295.9 K 295.9 K 295.7 K P, atm (-)0.83888 (-)0.83888 (-)0.83888 (-)0.81421 (-)0,78954 (-)0.78954 (-)0.76487 (-)0.71551 (-)0.64150 (-)0.56748 T/V 4543.846 4922.5 5370 5907 6565.556 7386.25 8384.286 9851.667 11822 14777.5 Abs P 0.16112 0.16112 0.16112 0.18579 0.21046 0.21046 0.23513 0.28449 0.3585 0.43252 ▬▬▬▬▬ Pressure 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 0 2000 4000 Abs P & TAV 6000 8000 10000 Temperature/Volume y = 2.9830E-05x R²9.9743E-01 12000 14000 16000