Answer:
The number of quarters required to pile up to 2 km are 1000000.
Step-by-step explanation:
Diameter of each quarter = 2 mm
Total height = 2 km
Number of quarters required is given by
[tex]\frac{ 2 km}{2 mm}\\\\\frac{2\times 1000\times 1000 mm}{2 mm}\\\\= 1000000[/tex]