= Solution
For a grazing <null geodesic>, take the <impact parameter> as $b\simeq R=6.0\times10^6\,\mathrm m$. The leading <Schwarzschild light deflection> is
$$
\delta=\frac{4GM}{bc^2}.
$$
With the <gravitational constant> $G\simeq6.6743\times10^{-11}\,\mathrm{m^3\,kg^{-1}\,s^{-2}}$ and <speed of light> $c\simeq2.998\times10^8\,\mathrm{m\,s^{-1}}$,
$$
\boxed{\delta\simeq9.9\times10^{-4}\,\mathrm{rad}\simeq0.0567^\circ\simeq204\text{ arcsec}\simeq3.4\text{ arcmin}.}
$$
Here $GM/(Rc^2)\simeq2.5\times10^{-4}\ll1$, so the weak-field approximation is appropriate. A ray passing at a larger <impact parameter> has a correspondingly smaller deflection.
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