Can you please assist me with the problems shown in the attached screenshot?

Figure 18 Evaluate the following sum. 1 8k =(Simplify your answer. Type an integer or a simplified fraction.) K =0 Figure 19 Write the series 2 + 3+ 4 + 5 + 6 using summation notation with a) The summing index k starting at k = 1. b) The summing index j starting at j = 0. a) 2+3+4+5+6= > K = 1 (Simplify your answers.) b) 2+3+4+5+6 = = >[ j= (Simplify your answers.) Figure 20 Write the series below using summation notation with the summing index k starting at k = 1. 27 28 n + 25 26 + 2 3 n 27 28 n + 25 26 + 2 3 n k = 1 (Simplify your answer.)