Can Someone Help Me With Homework Please?

It's A Bit Confusing.

(The ......Are Blanks You Have to fill in)
The main impurity in hematite is normally.....?
When........is added is added to the blast furnace it reacts with the silica to form a molten substance called.........?
The..............has a lower.............and floats on top of the molten iron.

True Or False:
-all ores contain 50% metal
-coke is a good source of the element carbon
-the less reactive a metal is the harder it is to remove from its compound.
-in the blast furnace carbon monoxide is oxidised to carbon dioxide
-molten iron has a lower density so its sinks to the bottom of the blast furnace where it can be removed

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Meh.