Without graphing, tell whether each quantity is changing at a constant amount per unit interval, at a constant percent per unit
interval, or neither. Justify your reasoning.

1. A bank account started with $1000 and earned $10 interest per month
for two years. The bank then paid 2% interest on the account for the
next two years.

2. Jin lu earns a bonus for each sale she makes. She earns $100 for the first sale, $150 for the second one, $200 for the third one and so on.