For lineage a, how many speciation and extinction events occurred from 2 million years ago to time 0?

I found the problem. 

Lineage a had 5 speciation events and 5 extinctions.

Speciation events are  events that splits the lineage and produce two or more separate species. 
Extinction events are events where the whole species die out in a short span of time. It is called "the great dying".

In the image,speciation is represented when one line breaks into two lines. Extinction is represented with the dagger symbol.

The  ancient egyptians  who  built the pyramids  may have been  able  to move massive stone blocks across the desert by wetting the sand in front of a contraption  built  to pull the heavy objects