standard_description: Apply geometric methods to solve design problems (e.g., designing an object or structure to satisfy physical constraints or minimize cost; working with typographic grid systems based on ratios).
problem_activity: Task
About how many cells are in the human body?
You can assume that a cell is a sphere with radius 10$^{-3}$cm and that the density of a cell is approximately the density of water which is 1g/cm$^3$.


aligns: no