Suppose a star is $4\mathrm{.}351018$ m from Earth. Imagine a pulse of radio waves is emitted toward Earth from the surface of this star. How long $($in years$)$ would it take to reach Earth?

years

$($b$)$

The Sun is $1\mathrm{.}501011$ m from Earth. How long $($in minutes$)$ does it take sunlight to reach Earth?

minutes

$($c$)$

The Moon is $3\mathrm{.}84108$ m from Earth. How long $($in s$)$ does it take for a high$-$intensity laser beam to travel from Earth to the Moon and back?

s