To develop this problem we will apply Newton's laws regarding gravitational forces, both in space and on earth. From finding this relationship, leaving the variable of the dust mass open, we will find the relationship of the forces between the two surfaces. Our values are,



Distance between the center of lead sphere to dust particle



Gravitational force of the sphere on the dust particle:



Weight of the dust particle


Ratio of F and W:


Therefore the ratio is 
Answer: 216.2 J
Explanation: The heat energy of copper is the expressed in Q=mc∆T. First make sure that the mass 0.0693 kg is converted into grams to cancel both units.
Q= 69.3 g x 390 J/g°C x 26 °C-18°C = 216.2J
Check the picture below.
now, for 6 triangles, well, simply 6*6.
All living things are made up of one or more cells. They are the basic unit of life.