Answer:
28.705 cm
Explanation:
Hello,
In this case, for rounding the number to five significant figures we must "cut" it at 5 so we hide the 3, therefore it turns out:
28.705 cm.
Moreover, we must realize that since such 3 is less than five, we do not modify the previous five to six, case which would happen if that three has changed to five or more.
Regards.
