Identifying substances

Note: You should solve this problem first: Wrong setup? in order to understand the below problem.

Given a setup below:

Identify A, B, Y, Z.

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These are the substances that may help you with the problem:

• 1) $HCl$

• 2) $MnO_2$

• 3) $NaCl$

• 4) $H_2SO_4$

• 5) $MgCO_3$

• 6) $HNO_3$

If you think 4 of the 6 substances are indeed the ones you need to identify, type the answer in the following order: A - B - Z - Y (example: if you match A-1, B-2, Z-3, Y-4 then you type 1234)

If you think at least one of A, B, Z, Y must be some substances other than those mentioned, type 0.