(-1)^(k+1) * (1/2^k) (HELP!!!!!)

[RideGMAT]

Plz help me solve this problem from GMAT Prep:

For every integer 'k' from 1 to 10, inclusive, the kth term of a certain sequence is given by (-1)^(k+1) * (1/2^k). If 'T' is the sum of first 10 terms in the sequence, then 'T' is:-

(a) Greater than 2
(b) Between 1 & 2
(c) Between 1/4 & 1
(d) Between 1/4 & 1/2
(e) Less than 1/4


OA is (d)

[iamcste]

Plz help me solve this problem from GMAT Prep:

For every integer 'k' from 1 to 10, inclusive, the kth term of a certain sequence is given by (-1)^(k+1) * (1/2^k). If 'T' is the sum of first 10 terms in the sequence, then 'T' is:-

(a) Greater than 2
(b) Between 1 & 2
(c) Between 1/4 & 1
(d) Between 1/4 & 1/2
(e) Less than 1/4


OA is (d)

Pls refer here.

https://www.beatthegmat.com/gmat-prep-qu ... 21502.html

Additonal qtns not covered there, Kindly shoot