The multiple of the length of the long arm and the length of the short arm is the gravity of the earth/force exerted = 6*10^24kg*10N/kg=6*10^25N/600N=10^23 times
The second question is done using similar triangles, which is also 10^23 times 1cm.
That is 10^23cm=10^18km
10^18km/3*10^5km/s=3.33*10^12s=105699 years