A Child Psychologist Was Interested in the Difference in Age

Short Answer

A child psychologist was interested in the difference in age (in years) between a boy and girl when they first learn to ride a two-wheeled bicycle. The psychologist developed a 99% confidence interval for the difference in average ages to be (-0.58, 0.73). What conclusion, if any, can be drawn from this interval?
Since 0 is included in the interval, one ______________ conclude there is a difference in age, on the average, at which boys and girls first learn to ride a two-wheeled bicycle.