Answer
$6.67 \times 10^{-11} N$
Work Step by Step
$$F= G \frac{m_{1} m_{2}}{d^{2}} = $$
$$(6.67 \times 10^{-11} \frac {N \cdot m^{2}}{kg^{2}}) \frac{(1 kg)(1 kg)}{(1 m)^{2}} = $$
$$6.67 \times 10^{-11} N $$
This is discussed on page 163.