Answer:
<u>Recursive:</u>

<u>Explicit:</u>

Explanation:
<u>1. Sequence:</u>

<u>2. Recursive formula</u>
The recursive formula permits to calculate the value of the nth term in the sequence using the (n-1)th term in the sequence.

<u>3. Explicit formula</u>
The explicit formula permits to calculate any value of a term in the sequence:

A) interquartile range
The difference between the upper and the lower quartile is a measure of spread known as the interquartile range.
Part A
Your problem statement already shows you the conversion.
Bottles purchased: 5×10¹⁰
Bottles recycled: 8.3×10⁹
Part B
The ratio of bottles purchased to bottles recycled is
... (5×10¹⁰)/(8.3×10⁹) = 0.6×10¹ = 6.0
The number of bottles purchased is 6 times the number of bottles recycle.