Answer
a) 5
b) 5
c) 3
d) 2
Work Step by Step
a) 13001 has 5 significant figures since its a whole number and every digit is significant.
b) 13111 has 5 significant figures since its a whole number and every digit is significant.
c) $1.30\times10^{4}$ has three significant figures (i.e. all of the numbers are significant) since the zero is after the decimal place.
d) 0.00013 has two significant figures since all of the zeroes prior to the digits are insignificant and also there is no bar above the numbers to indicate significance.
