Answer:
![m\angle LMN=90^(O)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/y86dcoulbw2pe6s98eekpblbd1hq40ydub.png)
Explanation:
We know that the outside angle formed between two tangents of a circle can be found by taking half of difference of bigger arc angle and smaller arc angle.
We can express it as:
![m\angle LMN=\frac{m\widehat{LN}_(Bigger)-m\widehat{LN}_(Smaller)}{2}](https://img.qammunity.org/2019/formulas/mathematics/middle-school/pwpluoolxt59jh28rii49azf1vykaunpal.png)
From the given diagram, we get:
![m\widehat{LN}_(Bigger)=270\\m\widehat{LN}_(Smaller)=360-270=90](https://img.qammunity.org/2019/formulas/mathematics/middle-school/lwvy81bfa5i54nskp0qybdst3rpfhoscnb.png)
Upon substituting these values in the formula, we get:
![m\angle LMN=(270-90)/(2)=(180)/(2)=90\\m\angle LMN=90^(0)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/43dn8hc1un0wfcgq2zdvk2avwhgmox6fsb.png)