1) 7) $\sum _{1=1} ^{5}\left(3\right)$ 15 $\sum _{1=2} ^{5}\left(6t^{2}\right)$ $324$ 2) 8) $\sum _{k=1} ^{3}\left(6\right)$ 18 $\sum _{a=3} ^{6}\left(2a\right)$ $24$ 3) 9) $\sum _{1=1} ^{8}\left(2\right)$ 16 $\sum _{k=1} ^{5}\left(3k^{2}\right)$ $165$ 4) $10\right)$ $\sum _{1=2} ^{6}\left(5\right)$ 25 $\sum _{1=1} ^{5}\left(4i+2i\right)$ 80 5) $\sum _{1=3} ^{7}\left(8\right)$ 40 $11\right)\sum _{1=2} ^{5}\left(3i^{2}+2i^{2}\right)$ $270$ 6) $12\right)$ $\sum _{a=4} ^{6}\left(2\right)$ 6. $\sum _{1=1} ^{3}\left(3i+7i+5\right)$ 75