Answer:
Compute the number of gold atoms per cubic centimeter = 9.052 x 10^21 atoms/cm3
Explanation:
The step by step and appropriate substitution is as shown in the attachment.
From number of moles = Concentration x volume
number of moles = number of particles/ Avogadro's number
Volume = mass/density, the appropriate derivation to get the number of moles of atoms
Complete Question
The cars of a roller-coaster ride have a speed of 19.0 km/h as they pass over the top of the circular track. Neglect any friction and calculate their speed v when they reach the horizontal bottom position. At the top position, the radius of the circular path of their mass centers is 21 m, and all six cars have the same mass.V = -18 m What is v?X km/h
Answer:

Explanation:
Velocity 
Radius 
initial velocity u
Generally the equation for Angle is mathematically given by




Generally
Height of mass



Generally the equation for Work Energy is mathematically given by

Therefore


