welll...you have there written just one relationship...it is berween 280 and 4 hours...you have to figure out speed:

it is speed per hour
then you just connect time and speed:
- 140 - 2
- 280 - 4
- 350 - 5
- 420 - 6
- 560 - 8
- 700 - 10
Answer:
4
Step-by-step explanation:
pH = f(x) = -log₁₀x
1. Graphs
I used Excel to calculate the pH values and draw the graphs (see the Figure).
f(x) and f(x) +1 are plotted against the left-hand axis, while f(x+ 1) is plotted against the expanded right-hand axis.
The points at which pH = 0 and pH = 1 are indicated by the large red dots.
2. x = 0.5
When x = 0.5, pH ≈0.30. The point is indicated by the red diamond.
3. Transformations
(a) ƒ(x) = -log(x) + 1
This function has no y-intercept, because log(0) is undefined.
(b) ƒ(x +1) = -log(x + 1)
f(0) = -log(0 + 1) = -log(1) = 0
This function has a y-intercept at (0,0).
hope this helps please mark me brainliest!
The first one is 10ab + 20