Which of the following ancient greece made great advances in the field of mathematics

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

Which of the following is the best description of lesion

How did brunelleschi solve his problem with the dome of the florence cathedral? a. he created an outer support shell. b. he created many layers of support within the dome. c. he created external supports for the dome. d. all of the above