If a question asks what is the sum of all powers of 2... for example what is the sum of all powers of 2 that are less than 5 that are divisible by 2. This is silly example I know, but are they asking for the sum of the power eg in the set ${2^1; 2^2; 2^3}$ would the sum of powers of two be $1 +2 +3$ or $2+4+8$. Thanks.
EDIT this problem is about language not the actual numerical sum.
The powers of $2$ are $1, 2, 4, 8, 16$ and so on.
By inspection only the first few are less than $5$; namely $1,2,4$.
Only the last two of these are even and their sum is $2+4=6$.