Deductions & credits

Thank you for those instructions.  I do see the $25,700 on the 1040.  

 

The page I'm having a hard time finding is this one:  Get a tax break for donating cash to charity.  Once I find this and add the $600, will this impact the standard refund?

 

I do see on the 1040 that it has the $3085 as the refund, which is the same as what is listed as the Standard refund.  But the amount on the deduction page for itemized is $3126.  I'm curious what the difference is, and why I'm not able to toggle.