Answer:
Question A: The dimensions of the original painting are 42 cm by 126 cm.
Question B: The area of the original painting is

Question C: The dimensions of the painting in feet are 1.386 ft by 4.158 ft.
Explanation:
Question A:
The scale of the copy is
0.5 inches:12 centimeter.
This means that 1 inch on the scale is 24 centimeters.
Therefore the width of the original painting is:

and the height of is:

Therefore the dimension of the original painting are 42 cm by 126 cm.
Question B;
The area of the original painting is just width multiplied by height:

Question C:
We convert the dimensions of the painting from centimeters to feet:


Therefore the dimensions of the original painting in feet are 1.386 ft by 4.158 ft.