Given z = 4(cos(pi/2)+ isin(pi/2)), what is z^3

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Part a : solve -vp + 40 < 65 for v part b : solve 7w - 3r = 15 for r show your work .

Arianna is buying plants for her garden. she buys 15 flowering plants for $96. pink flowering plants sell for $8, and purple flowering plants sell for $5. how many pink flowering plants did arianna buy? i figured out the answer! the answer is 7. 8x +5y = 96 plug in 7 for x 8 (7) + 5y = 96 56 + 5y = 96 subtract 56 from both sides 5y/y = 40/5 y = 8 she bought 7 pink and 8 purple plants

(fog)(x) if f(x)=x^2- 4 and g(x)=x^2 + 2 x, f(g(x))= f(x^2+2x) (x^2+2x)^2-4 (x^2+2x)(x^2+2x)-4 (x^4+2x^3+5x+4x^2)-4 x^4+2x^3+4x^2+5x-4 what am i doing wrong