Answer
1 in.; 0.5 in.; 0.00329; 0.33%
Work Step by Step
For the given measurement, we have
The precision is 1 in
The greatest possible error is one-half the precision
$0.5\cdot 1\ in=0. 5 \ in$
The relative error is
$relative~error=\dfrac{greatest~possible~error}{measurement}$
$\frac{0.5\ in}{12 \ ft 8\ in}=\frac{0.5\ in}{152\ in}=0.0033$, (we used the fact $1 ft =12 in$)
The percent of error is $0.33\%$.
