20=2*10
500=5*10*10
20*500=
2*10*5*10*10=
2*5*10*10*10=
10*10*10*10=
10000
4 zeroes
(2n+7)(n+1)(n-1). So the first one.
A.1. Answer= The decimal does appear to have a repeating pattern because, the numbers after the decimal keep going on and on.
A.2. Answer= 1.345345634567 is a rational number. My reasoning is, every positive number is a rational number.
Hope this helps!! :D