Rental house appliance expense percentage

I looked through the similar topics but did not see......

 

We purchased a new refrigerator for our rental property.

 

When I entered the cost as an "expense" (not a depreciated asset), the top display Tax Due/Refund only changed by 10% of the $750 I entered.

 

Why?

 

I also can't find a chart of which expenses for rentals or business (we have multiples of each) are deductible at any given percentage. is one available somewhere?

 

Thanks

I also can't find a