because they are very hard
It isn't. The inner core is solid, the outer core is liquid.
No. The inner and outer core are both composed primarily of iron and nickel, but the outer core is liquid and surrounds the inner core. The inner core is the innermost layer of Earth and is kept solid by the enormous pressure.
the solid inner core and the liquid outer core
outer core is liquid whereas the inner core is solid
outer core is liquid whereas the inner core is solid
The inner core is a solid, and the outer core is a liquid.
This question is based on a false assumption that the outer core is solid and the inner core is liquid. This is incorrect. It is in fact the inner core that is solid (and so is the most dense) and the outer core which is liquid.
No it is believed that the inner core is solid and it does not.
The inner core is solid.
No. The inner core is considered a solid.
Earth's inner core is solid.
the inner core is a liquid where as the crust is a solid :)