11) a =- 2 12) a =-11 + 2n n+ 2 Evaluate each series. 13) [ k(K - 2 ) 14 ) _ (400 - m? ) m =0 15) E (300 - n2 ) 16 ) 2 5m 17) M- 5 a 18) _ (400 - k) Find the missing term or terms in each arithmetic sequence. 19) ..., -18, -46, ... 20) ..., -12, 28, ... Find the missing term or terms in each geometric sequence. 21) ..., - 3, -48, ... 22 ) ... . - 2, -512