I have no idea what to do and why it won't work it says something about a string but I have tried and nothing is working please help :)

as follows: >=x (^) For example, a rate of 1.5 means that there would be 15 fish after 1 year if the particular pond was seeded with 10 fish. =10(1.51)=15 There would be roughly 576 fish after 10 years. =10(1.510)=576.65 the correct assignment to the pond_1 variable looks like this: pond_1 = pop_after_n_years (INIT_POP_POND_1, YEARLY_GROWTH_POND_1, YEARS) In TOD0 4 , you will define the total_population variable and assign it the sum of the pond_1 - pond_5 variables defined earlier