Answer:
Let 'a' be the first term, 'r' be the common ratio and 'n' be the number of terms
Series = 2+6+18.......= 2+2•3¹+ 2•3².......= 728
Now,

So,

Therefore, number of terms is 6
The # halfway in between 21 and 63 is 42.
Answer:
I think that the answer is 50 because 100 divided by 2 equals 50
Step-by-step explanation: