Can anyone me solve this problem? i'm confused and stuck

In triangle abc, the length of side ab is 12 cm, the length of side bc is 5 cm, and the length of side ca is 9 cm. find the measure of angle a using the law of cosines.

An apartment has a replacement cost of $950,000 and contents valued at $1,450,000. it has a classification of a and a territory rating of 3. find the annual premium a) $10,185 b) $9,230 c) $3,155 d) $13,830

What is always true about a positive integer raised to a negative odd power?