Answer
1 oz, 0.5 oz, 0.00649, 0.65 %
Work Step by Step
For the given measurement, we have
The precision is 1 oz
The greatest possible error is one-half the precision
$0.5\cdot 1\ in=0. 5 \ oz$
The relative error is
$relative~error=\dfrac{greatest~possible~error}{measurement}$
$\frac{0.5\ oz }{4\ lb \ 13\ oz }=\frac{0.5\ in}{77\ in}=0.00649$, (we used the fact $1 lb =16 oz$)
The percent of error is $0.65\%$
