Which of the following pairs of metal and its ore is correct?

Which of the following minerals does not contain iron?

Cryolite is an ore of

Which of the following set of elements mostly occur as sulphide ores?

Among the following ores: Bauxite,Siderite,Cuprite,Calamine,Haematite,Kaolinite,Malachite,Magnetite,Sphalerite,Limonite,Cryolite,the number of principal ores of iron is $......$

Identify the metals present in brass.