Let's analyze the problem step by step with the given balances:
1. For January 2014, the balance is -45 dollars.
2. For February 2014, the balance is 150 dollars.
3. For March 2014, the balance is 15 dollars.
4. For April 2014, the balance is not given.
To answer the question regarding the highest balance, we can compare the provided balances for January, February, and March 2014.
The balances are:
- January: -45 dollars
- February: 150 dollars
- March: 15 dollars
Comparing these amounts, the highest balance is 150 dollars.
Therefore, the correct answer for the highest balance Kelly had at the beginning of any month is \[tex]$150.
The complete and correct answer should fill the blank as follows:
The highest balance Kelly had at the beginning of any month was \$[/tex] 150.