Cant figure out this accounting problem and its driving me insane.

compute the missing amount (?) for the company (adapted and in billions).

FedEx Corporation:
BEGINNING
Assets..........$12
Liabilities......7

ENDING
Assets..........$13
Liabilities..... 7

OWNERS EQUITY
Issuance of stock......$?
Dividends.......1

INCOME STATEMENT
Revenues........$20
Expenses........19

I'm supposed to use this formula: Assets = Liabilities + Owners Equity.

The book says the missing value is 1. How can this be?