Write if each is a balanced or unbalanced force:
-2 people pulling opposite directions on a rope w/the same amount of force
-2 women lifting a box into the back of a truck
-a hook sitting high upon a bookshelf
-an earthquake releasing energy at a fault line
-a moon that orbits a planet

d.) circle motion requires a force to give it a centripetal acceleration.

the density of gold = 19.3 g/cm3

the relation between density and mass and volume is

density = mass / volume

given :

mass of gold = 13 g

density = 13g / volume = 19.3

volume = 13 /19.3 = 0.67 cm^3

thus volume of gold nugget = 0.67 cm^3

level 4 to level 2 : ))