In determining the number of significant figures in a given number, there are three rules to always remember / follow:
First: All integers except zero are always significant.
Second: Any zeros located between non zeroes are always significant.
Third: A zero located after a non zero in a decimal is always significant whether it is before or after the decimal
Therefore using this rule, the number of significant digits in the given numbers are:
(a) 214 = 3
(b) 81.60 = 4
(c) 7.03 = 3
(d) 0.03 = 1
(e) 0.0086 = 2
(f) 3236 = 4
(g) 8700 = 2