#### Answer

mean=2.83,median=27.5,mode=2.9,2.8 and 2.7,range=0.7

#### Work Step by Step

After finding the length of the crocodile in 4 years your data points are 2.8, 2.9, 2.9, 2.7, 3.2, 2.8, 2.7, 2.8, 2.5, 2.7, 2.9, 3.1.
To find the mean you have to add all the number together and divide by 12(the numbers of data points): $\frac{2.8+2.9+2.9+2.7+3.2+2.8+2.7+2.8+2.5+2.7+2.9+3.1}{12}$=2.83.So the mean is 28.3.
To find the median you have to arrange the values from the least to the greatest ( 2.5, 2.7, 2.7, 2.7, 2.8, 2.8, 2.8, 2.9, 2.9, 2.9, 3.1, 3.2). So the middle value is 2.8 and 2.7. To find the median between the two, you have to find the average:(2.8+2.7)/2=2.75. So the median is 2.75
The mode is the numbers which repeat the most which are 2.9,2.8 and 2.7.
The range is the largest number minus the smallest number so 3.2-2.5=0.7