Answer:
1.721 ×

Explanation:
A number expressed in scientific notation is of the form
a ×

where 1 ≤ a < 10 and n is an integer
Given
17, 210, 000, 000 , then
= 1.721 ×
The decimal point has to be moved 10 places to the right of where it has been repositioned.
A move to the right is + while a move to the left is -
1.721 ×
← in scientific form