A scientist is studying the cell cycle of human skin cells, where one complete cycle takes 12 hours.
Figure 1 shows the relative proportion of time spent in each of the three stages of this cell cycle (Stage A, Stage B, and Stage C).

What percentage of the total time of the cell cycle is spent in Stage A?
If a single skin cell divides to form two new cells every 12 hours, how many hours will it take for one original cell to divide and form a group of 16 cells?