Answer
a. $0.12$
b. $0.52$
c. $1.18$
Work Step by Step
a. 54.78% of the area under the distribution curve lies to the left of it.
Use Table E, an area of 0.5478 corresponds to a z value of $0.12$
b. 69.85% of the area under the distribution curve lies to the left of it.
Use Table E, an area of 0.6985 corresponds to a z value of $0.52$
c. 88.10% of the area under the distribution curve lies to the left of it.
Use Table E, an area of 0.8810 corresponds to a z value of $1.18$