8) for the geometric series defined by t1= 1and tn = 5^(n-1)the number of terms that will sum to 19531 is :
a) 7
b) 6
c) 2
d)3

step-by-step explanation:

answer: the angel abc is 30°,and the abc is a triangle where the angel bac is 90°

so ac is the half of 24=12ft,and from the pythagorean theorem we find ba

ba=√bc^2-ac^2=√576-144=√432=12√3ft

so bac is 12+12√3=12(1+√3)ft

the answer is 8.64

step-by-step explanation: