I believe it's B. the transmission of heat across matter
Your answer is friction. Friction between to object slows the object down.
Let's call this "certain amount" with a variable, x, (since it's not specified in the question, I will assume that the answer shall just be based on this variable).
So every additional floor will make the building sink by x, and let's make the unit cm, so x cm.
Now we know that the maximum depression is 20 cm, and it is also
x*y, where y is the number of floors.
So we have x*y=20,
therefore the number of floors is:
20/x or This is the answer
Answer:
they would repel because they have the same charge. Charges that are different will stick together.
