Urgent! Income Tax questions?

Urgent! Income Tax questions?
Can you tell me how to answer these questions? Can you teach me how the number coming from? Thank you sooo much. Jim(age 50) and Martha (age 49) are married with three dependent children. They file a joint return for 2005. Their income from salaries totals $140,000 and they received $10,000 in taxable interest, $5,000 in royalties and $3,000 of other ordinary income. Jim and Martha's deductions for adjusted gross income amount $7,500 in state income taxes and $4,500 in investment interest expense. Calculate the following amounts. a.What is the amount of their gross income? .b.What is the amount of their adjusted gross income? c.Itemized deduction or standard deduction amount d Number of exemptions e Taxable income f Income tax liability