#### Answer

(a) $1.9$
(b) $88$
(c) $0.0047$
(d) $8800$
(e) $1.8 \times 10^{5}$

#### Work Step by Step

1. Identify the third significant figure (the one we are going to drop):
(a) $1.8\underline5 4$
(b) $88.\underline2 0 38$
(c) $0.0047\underline 38 265$
(d) $88\underline 0 7$
(e) $1.8\underline 3 2$
2. Remove* the third SF and all the digits to its right. If this digit is greater or equal to 5, add 1 to the third digit.
* If the digits are on the left of the decimal point, just substitute them by a "0".
(a) $1.9$
(b) $88$
(c) $0.0047$
(d) $8800$
(e) $1.8$