Answer:
D. 46.5 in.–73.5 in.
Step-by-step explanation:
We have been given that horn lengths of Texas longhorn cattle are normally distributed.


Since the empirical rule states that about 99.7% of the population lies within the 3 standard deviation. So according to normal distribution the range for the middle 99.7% of the values is:
.
Upon substituting our given values we will get,
![[60\text{ inches }-3*4.5\text{ inches },60\text{ inches }+3*4.5\text{ inches }]](https://img.qammunity.org/2020/formulas/mathematics/high-school/gq0nhjkxoig06c8f6dnbrtpo3nwdwsba1e.png)
![[60\text{ inches }-13.5\text{ inches },60\text{ inches }+13.5\text{ inches }]](https://img.qammunity.org/2020/formulas/mathematics/high-school/xav53pyord17f5fsifb2la4pvxe1pkggnd.png)
![[46.5\text{ inches },73.5\text{ inches }]](https://img.qammunity.org/2020/formulas/mathematics/high-school/pwxv6mmh4s4ucsvmkaizhd69ogcud2ybua.png)
Therefore, the range of horn lengths for the middle 99.7% of Texas longhorn cattle is 46.5 inches to 73.5 inches and option D is the correct choice.