Howell and Newcombe examined 6 month old infants who were low birth weight babies when they were born. Each child...

Howell and Newcombe examined 6 month old infants who were low birth weight babies when they were born. Each child was rated on the Bayley Psychomotor Development Index. The population mean for this test is 100 and high scores mean better performance Perform a t test, calculate the effect size index and write a conclusion about what to expect ( on the average) of low birth weight babies.