Okay, here we have this:
Considering the provided figure, we are going to calculate the surface area, so we obtain the following:
So to calculate the surface area, we will substitute with the given data in the following formula:
Surface Area=Area of the lower rectangle + Area of the upper rectangle + Area of the lateral triangles + Area of the posterior rectangle
Surface Area=(1m * 0.8m)+(1m*0.81m)+2(0.1m*0.8m/2)+(0.1m*1m)
Surface Area=(0.8m^2)+(0.81m^2)+2(0.04m^2)+(0.1m^2)
Surface Area=(0.8m^2)+(0.81m^2)+(0.08m^2)+(0.1m^2)
Surface Area=1.79m^2
Finally we obtain that they did use 1.79m² to cover the ramp including the bottom.