2) b + bx +bx^2 +bx^3 .... +bx^9 = 180, where x =7/4

Therefore, b= 47185920/93808891

Therefore, b_2+b_4+b_6+b_8+b_10 = **1260/11.**

1) By the geometric series (finite) formula,

\(\frac{8000(1-(-1.5)^n)}{2.5}=57875 \\ \text{where n is the number of terms}\)

n=7, so 8000 times -1.5^7 = **-136687.5.**