Answer:
b. 2 cans of ink
Explanation:
In order to calculate the number of cans you need to paint the complete wall, you first calculate the area of the wall by using the information about its width and height:
With one can you can paint 10m^2 of wall, with two cans you can paint 20m^2, which is enough to paint the wall of 12.5m^2.
Then, you need only two cans of ink
b. 2