Step 1
Given;

Required; To find the difference in interest between the two periods.
Step 2
State the formula for simple interest

Step 3
Find the interest when the rate is 8%

Therefore the interest is given as;

Step 4
Find the interest in 1980 with a 20% rate

The interest is given as;

Step 5
Find the difference in interest between the two rates.

Hence, the difference in interest between the two rates = $11095.89
Answer:
<h2>d(P, Q) = 6</h2><h2>d(Q, R) = 5</h2>
Step-by-step explanation:
The formula of a distance between two points A(a) and B(b):
<h3>d = |b - a|</h3>
We have P(x + 3), Q(x- 3), R(x + 2).
Substitute:
d(P, Q) = |(x - 3) - (x + 3)| = |x - 3 - x - 3| = |-6| = 6
d(Q, R) = |(x + 2) - (x - 3)| = |x + 2 - x - (-3)| = |2 + 3| = |5| = 5