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:
d. steam-water equilibrium at 373 K
Step-by-step explanation:
At one atmospheric pressure , the boiling point of water is 100°C or 273+100 = 373 K in kelvin temperature scale.
so at this temperature vapor pressure of water and steam are in equilibrium .
The answer is(4 -3.5x-15)hope this can help
The answer or range would be 40