It is a simple question. In fact I though it was really simple, but when I tried I could not make it work. I am sure I am missing something but I do not what.
For example:
<div>I have 4 walls, two walls have Marca(Mark): 30 and the others Marca(Mark):60.</div>
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<div>Just I want to convert to solid the wall with 30 value.</div>
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<div>Thank you in advance.</div>
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