We will solve this in “Conceptual Way”.
Basically Initially the Bucket has 16Mb .
Now a Bulk of data appears and we can given them Token Directly (Required Time =0)
These 16Mbits can be send in 10Mb/sec.
That Will need 1.6 secs.
Now, In this 1.6 secs We can create “Tokens” at a speed of 2Mbps
So, In 1.6 sec we can create 3.2Mbits tokens
To transfer it in The 10Mbps we need .32 secs
Again in .32 sec we can create .64 Mbits
that can be send in .032 secs
In this Way we can proceed but the time Will be too smaller
And Finally the Time at which Highest Speed can be Used Becomes (1.6+0.32+0.032+…..)secs
Finally 2 secs.