Divisibility by 8 when converted in base 10

Divisibility by 8 when converted in base 10

How many 7-digit numbers are there in binary(base-2)? How many of them are
divisible by 8 when converted to base 10?
Someone told me this question is very simple but I am stuck on second part
and can't seem to find the answer.
My approach:
In binary system, only two digits are there i.e. 0 and 1. So except for
the first place, all the renaming 7 places can be filled by either 0 or 1.
As first one can't be zero so it can be filled in only one way. So.
1x2x2x2x2x2x2 = 64
Now, I don't know how to approach the second part, please assist in same.
Answer for second part is 8.