In the geometric sequence with a1=64a_1 = 64a1=64 and r=−12r = -\frac{1}{2}r=−21, which terms are negative?
All odd-positioned terms (a1,a3,a5,...a_1, a_3, a_5, ...a1,a3,a5,...)
All even-positioned terms (a2,a4,a6,...a_2, a_4, a_6, ...a2,a4,a6,...)
No terms are negative
Alternates in an unpredictable way