geometric series??

(a)Given two series S1 and S2:
S1:a+ar+ar^2+......+ar^n-1
S2:a^2+(ar)^2+(ar^2)^2+......+(ar^n-1)^2
where S1 is a geometric series of n terms with a being the first term and r being the common ratio.
(i)Is S2 a geometric series ?
(ii)Show that if the sum of S1 is Z,then the sum of S2 is {a(1+r^n)/1+r}*Z.
(b)If the sum of the first 10 terms of the geometric series
x+2x+4x+.....is 3069,find
(i)the value of x;
(ii)the sum of the first 10 terms of the series
x^2+(2x)^2+(4x)^2+......