What is true for two pieces of iron at same temperature

Frictional forces acting on an object are often converted into energy, which causes the temperature of the object to rise slightly.

Why does the sun appear to be the brightest star in the sky? a- its apparent brightness is much greater than other stars. b- it burns more gas, making it brighter than any other star. c- it is the largest star in the galaxy, so it is the brightest star. d- its relative distance to earth is closer than the other stars.

Which compound contain an iron with a 3+ charge