Respuesta :

No, it's not written in scientific form because it has to be like this :
#1-10•10^#
So for 1, A is correct.

2.       1.22•10^8

3.       2.87•10^-2
I believe the first one is yes, it is written in scientific notation. 
1.22 x 10^9 is written in scientific notation
2.87 x 10^-2 is written in scientific notation