Help please! I dont know what im doing wrong
A study prepared for a Sunbelt town's Chamber of Commerce projected that the population of the town in the next 3 years will grow according to the rule
P(t) = 58,000 + 23t^(3/2) + 17t
where P(t) denotes the population t months from now. By how much will the population increase during the next 8 months? During the next 14 months?(Round your answers to the nearest whole number.)

I plugged t with 8 and 14 and it said 58656 and 59443 was wrong!

Question

Help please! I dont know what im doing wrong
A study prepared for a Sunbelt town's Chamber of Commerce projected that the population of the town in the next 3 years will grow according to the rule
P(t) = 58,000 + 23t^(3/2) + 17t
where P(t) denotes the population t months from now. By how much will the population increase during the next 8 months? During the next 14 months?(Round your answers to the nearest whole number.)

I plugged t with 8 and 14 and it said 58656 and 59443 was wrong!