" (a) "(s+4)(s-4)=......

If S_(1), S_(2), S_(3),….., S_(n) are the sum of infinite geometric series whose first terms are 1,3,5…., (2n-1) and whose common rations are 2/3, 2/5,…., (2)/(2n +1) respectively, then {(1)/(S_(1) S_(2)S_(3))+ (1)/(S_(2) S_(3) S_(4))+ (1)/(S_(3) S_(4)S_(5))+ ........."upon infinite terms"}=

If S_(1), S_(2), S_(3),….., S_(n) are the sum of infinite geometric series whose first terms are 1,3,5…., (2n-1) and whose common rations are 2/3, 2/5,…., (2)/(2n +1) respectively, then {(1)/(S_(1) S_(2)S_(3))+ (1)/(S_(2) S_(3) S_(4))+ (1)/(S_(3) S_(4)S_(5))+ ........."upon infinite terms"}=

Which of the following reactions will not occur? Why not? (a). MgSO_(4)(aq)+Cu(s)toCuSO_(4)(aq)+Mg(s) (b). CuSO_(4)(aq)+Fe(s)toFeSO_(4)(aq)+Cu(s) (c). MgSO_(4)(aq)+Fe(s)toFeSO_(4)(aq)+Mg(s) .

The area between the parabolas y^2 = 4x and x^2 =4y divide the square formed by the lines x=4 , y=4 and oxes into three parts . If the area of these three parts from uppar to bottom is S_1 ,s_2 and S_3 then S_1 : S_2 :s_3 =..........

Let S_n=1+2+3++n and P_n=(S_2)/(S_2-1)*(S_3)/(S_3-1)*(S_4)/(S_4-1)* . . . *(S_n)/(S_n-1) Where n in N ,(ngeq2)dot Then lim_(n→oo)P_n=______