Yes it can be a direct variation. it follows the form y = kx
The only variable that cannot be held constant is F, but we can hold the mass constant and vary the acceleration OR we can hold the acceleration constant and vary the mass. Either one would work, but the easiest would be to vary the mass and hold the acceleration constant since we are all pulled by the same action gravity
The ration is 12 muffins to every 21 donuts
The answer would be 24 because 24-4 is 20
To find the surface area of the open net, you’ll have to find the area of the faces
So, since there are 6 boxes you’ll have to find the area of the faces and add it up to find the surface area
10x4=40x4=160
3x4=12x2=24
160+24=184
Hope this helps ;)