<em>The question isn't complete. This is just part of the question</em>
<em>So please send the whole question together.</em>
Ok so to find the ratio just do 12/16 = 3/4. that's your common ratio.
The formula for sum of infinite :
a / (1 - r)
a is the first term and r is the ratio
which is
16 / (1 - (3/4))
which is
16 / (1/4)
16 * 4
which is 64
Answer:
The exterior angle is 35° + 62° = 97°
And 97° > 35°
And 97° > 62°
Step-by-step explanation:
Assuming the series is

The series will converge if

We have

So the series will certainly converge if

, but we also need to check the endpoints of the interval.
If

, then the series is a scaled harmonic series, which we know diverges.
On the other hand, if

, by the alternating series test we can show that the series converges, since

and is strictly decreasing.
So, the interval of convergence for the series is

.