Answer:
3² or 9
Step-by-step explanation:
Step 1: Add exponents

Step 2: Subtract exponents
You should get 3² because of exponent rules. Remember when you multiply exponents you add the powers and when you divide exponents you subtract the powers.
a) Sammie earns
£320×4% = £12.80
each year.
Joel earns
£420×3% = £12.60
each year.
Sammie earns the most interest.
b) Joel's interest after 5 years is
£12.60×5 = £63
so the total amount of money Joel will have is
£420 +63 = £483
Please be a little more specific on what you want to ask.
I can be of some help.
Step-by-step explanation:
the photo should explain