locations of objects always use estar

"Ahí" is 'far away', and "alli" is 'very far away'. It would not make sense for the shoe to be very far away, so you use "ahi". Hope this helps. :)

In this sentence, "está" means "currently is." I believe you are thinking of the other "esta/este/esto" meaning "this."

Estar is a verb so the ending depends on how it's conjugated, not the gender.

It sounds really awkward. It would be the equivalent of "The shoe of mine is not there" in English.

Also, keep in mind that "my" = «mi» and "mine" = «mío»

• Este es mi zapato - This is my shoe
• Este zapato es mío - This shoe is mine

alli - there, aqui - here

allá is correct, report it in the option "my answer shold be accepted"

In short, «allá» is farther away than «allí».

It might help to think of it like you would say in English, "Oh, it's right there", that is typically the same sentiment as «allí». On the other hand if you would say "Oh, it's over there" in English, «allá» is more appropriate.

Also, if you're talking about great distances like "Over there in Russia", «allá» is the correct term to use.

Here is the actual definition from the RAE:

1. adv. l. allí. Indica lugar menos circunscrito o determinado que el que se denota con esta última voz. Por eso allá admite ciertos grados de comparación que rechaza allí. Tan allá, más allá, muy allá. Se emplea a veces precediendo a nombres significativos de lugar para denotar lejanía. Allá en Rusia. Allá en América.