help with these two questions would be appreciated.

Question

1. Each year, Anna’s salary is increases by . It is £30,000 and in 2008 and £45,000 in 2018. Determine the annual increase percentage ? What is her salary in 2023? (Round your answer to two decimal places).
2. At a high-street shop, current sales revenue is £,50,000 per month. Provided it decreases by 1% every month, what will it be in one year? What is the equivalent percentage change in sales revenue after one year? (Round your answer to two decimal places).

Answer 1

a)

A=A₀e^kt

After 10 years

45000 = 30000e^10k

k= ln(1.5)/10

A(t) = 30000(1.5)^k/10

In 2023, after 15 years

A(15) = 30000(1.5)^1.5 = £55113.52

b)

A=A₀(1-r)^t

A(t) = 50000(1-.01)^t = 50000(0.99)^t

A(12) = 50000(0.99)¹² = £44319.24

Change = (50000-44319.24)/50000 = 0.1136 = 11.36%