Which of the following is not stage in the development of a thunderstorm

The formation of thunderstorm takes place through a cycle. It has three stages. Cumulus stage, Mature stage and dissipating stage are the three stages. Strong updrafts act to build up storm in the first stage.Heavy precipitation and winds are experienced in second stage. It gets weakened in the third stage.

Idid the calculation and i get 875,000,000 which can be written as 8.75 x 10^6?

Cis the