Answer
(a) 1
(b) 5
(c) 6
(d) 2
Work Step by Step
(a) In 5 x 10$^3$ m, there is one significant figure. Because the number is written with scientific notation, figuring out the significant figures is simple. The 5 is the only significant figure.
(b) In 5.0005 g/mL, there are five significant figures. All nonzero digits are significant as well as the three zeros between the nonzero digits.
(c) In 22.9898 g, there are six significant figures. All digits are significant because they are all nonzero digits.
(d) In 0.0040 V, there are two significant figures. The 4 is significant as well as the one trailing zero.
