Below is an instruction that describes a task. Write a response that appropriately completes the request in Swahili. Please answer in Swahili.

### Instruction:
A special balloon increases by two-fifths of its previous volume every hour when placed under water. If its original volume is 500cm³, what will its volume be after 2 hours underwater?

### Response:
 Katika saa ya kwanza chini ya maji, baluni itaongezeka kwa kiasi cha robo mbili ya 500cm³ ambayo ni (2/5)*500cm³ = <<2/5*500=200>>200cm³
Baada ya saa ya kwanza, itakuwa na kiasi cha (500+200)cm³ = <<(500+200)=700>>700cm³
Katika saa ya pili, itaongezeka kwa kiasi cha robo mbili ya 700cm³ ambayo ni (2/5)*700cm³ = <<2/5*700=280>>280cm³
Baada ya saa ya pili, kiasi chake kitakuwa (700+280)cm³ = <<(700+280)=980>>980cm³