How did gothic architects compensate for the lateral thrust of the cathedrals?

In the above painting by salvador dalí, entitled persistence of memory, which of the following objects do not occupy positive space? a. the clocks c. the tree trunk b. the ground d. the cliff select the best answer from the choices provided

Does anyone know how to balance two online classes at once when the deadline is may 10th?

1× 10×10×10+2×30×30=[tex]1 \times 10(4) + 2 \times 10(3) = \\ [/tex]