Suppose the 95% confidence interval for the average balance carried by customers who accept a certain credit card offer is ($1400, $2000). Which of the following is true? The mean balance of all customers could be $1000. 95% of all customers keep a balance of $1400 to $2000. The mean balance of 95% of samples of this size will fall between $1400 and $2000. The mean balance of all customer is between $1400 and $2000.