The weights for newborn babies is approximately normally distributed with a mean of 5.7 pounds and a standard deviation of 1.4 pounds.
Consider a group of 1400 newborn babies:
1. How many would you expect to weigh between 4 and 8 pounds?
2. How many would you expect to weigh less than 7 pounds?
3. How many would you expect to weigh more than 5 pounds?
4. How many would you expect to weigh between 5.7 and 9 pounds?

Step 1 ：Given that the weights for newborn babies is approximately normally distributed with a mean of 5.7 pounds and a standard deviation of 1.4 pounds. We are considering a group of 1400 newborn babies.

Step 2 ：We are asked to find how many babies we would expect to weigh between 4 and 8 pounds.

Step 3 ：To solve this, we need to use the properties of the normal distribution. The proportion of observations that fall within a certain range in a normal distribution can be found by calculating the z-scores for the endpoints of the range and looking up these z-scores in a standard normal distribution table or using a function that gives the cumulative distribution function (CDF) for the standard normal distribution.

Step 4 ：First, we calculate the z-scores for 4 and 8 pounds. The z-score is calculated as \((x - \mu) / \sigma\), where \(x\) is the value, \(\mu\) is the mean, and \(\sigma\) is the standard deviation. For 4 pounds, the z-score is \((-1.2142857142857144)\) and for 8 pounds, the z-score is \((1.6428571428571428)\).

Step 5 ：Next, we find the proportion of observations that fall between these z-scores. This is given by the cumulative distribution function (CDF) for the standard normal distribution. The proportion is \((0.8374744335450583)\).

Step 6 ：Finally, we multiply this proportion by the total number of babies to get the expected number of babies in this weight range. The expected number of babies to weigh between 4 and 8 pounds is approximately \(\boxed{1173}\).