I need help on this plz

To prove that def ~ gfh by the sss similarity theorem using the information provided in the diagram, it would be enough additional information to know that

(c) the diagram shows the first three shapes of a matchsticks arrangement. first shape = 3second shape = 5third shape = 7given m represents the number of matchstick used to arrange the n'th shape.(i) write a formula to represent the relation between m and n. express m as the subjectof the formula.(ii) 19 matchsticks are used to make the p'th shape. find the value of p.

What is the common difference for this arithmetic sequence? -6,-2,2,6,10 a.4 b.5 c.3 d.6