On Line 40, “Itemized deductions or standard deduction,” for 2017, the standard deduction is $6,350 for single filers and for married persons filing separately, $12,700 for joint filers and qualifying widow(er)s, and $9,350 for heads of household.
For Line 42, “Exemptions:” The amount for each exemption for 2017 is $4,050. Exemptions are reduced for taxpayers with AGIs in excess of the "applicable amount" ($313,800 for joint filers or a surviving spouse, $287,650 for a head of household, $261,500 for a single individual who isn't a surviving spouse, and $156,900 for marrieds filing separately).
For Line 45, “Alternative Minimum Tax”: Under Code Sec. 55(d), the AMT exemption amount for 2017 is $54,300 ($84,500 if married filing jointly or a qualifying widow(er); $42,250 if married filing separately). The AMT exemption amount is reduced if alternative minimum taxable income is above statutorily-defined amounts that depend upon filing status.
For Line 50, “Education credits from Form 8863,” in order to claim the American Opportunity Tax Credit, a taxpayer must provide the educational institution's employer identification number on Form 8863. A taxpayer should be able to obtain this information from Form 1098-T (Tuition Statement) or the educational institution.