Hi, can anyone me with question 4b? !

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.

The functions f(x) and g(x) are shown in the graph f(x)=x^2 what is g(x) ?

Griffin ordered a pair of sneakers online. he had a $22 credit that he applied toward the purchase, and then he used a credit card to pay for the rest of the cost. if the shoes cost $58, how much did griffin charge to his credit card when he bought the sneakers?