Answer:
The pressure of the gas 0°C is about 699.
Step-by-step explanation:
The given table of values is
Temperature Pressure
10 723
25 763
40 800
55 845
80 900
The general form of a trend line is
![y=a+bx](https://tex.z-dn.net/?f=y%3Da%2Bbx)
where, b is slope and a is y-intercept.
![b=\frac{\sum_{i=1}^nx_iy_i-n\overline{x}\overline{y}}{\sum_{i=1}^nx_i^2-n\overline{x}^2}](https://tex.z-dn.net/?f=b%3D%5Cfrac%7B%5Csum_%7Bi%3D1%7D%5Enx_iy_i-n%5Coverline%7Bx%7D%5Coverline%7By%7D%7D%7B%5Csum_%7Bi%3D1%7D%5Enx_i%5E2-n%5Coverline%7Bx%7D%5E2%7D)
![a=\overline{y}-b\overline{x}](https://tex.z-dn.net/?f=a%3D%5Coverline%7By%7D-b%5Coverline%7Bx%7D)
Using graphing calculator, we get
![a=699.006826](https://tex.z-dn.net/?f=a%3D699.006826)
![b=2.552218](https://tex.z-dn.net/?f=b%3D2.552218)
The equation of line of best bit is
![y = 2.552218x + 699.006826](https://tex.z-dn.net/?f=y%20%3D%202.552218x%20%2B%20699.006826)
where, y is pressure at x°C.
We need to find the pressure of the gas at 0°C.
Substitute x=0 in the above equation.
![y = 2.552218(0) + 699.006826](https://tex.z-dn.net/?f=y%20%3D%202.552218%280%29%20%2B%20699.006826)
![y =699.006826](https://tex.z-dn.net/?f=y%20%3D699.006826)
![y \approx 699](https://tex.z-dn.net/?f=y%20%5Capprox%20699)
Therefore the pressure of the gas 0°C is about 699.