#1) which digit is 10 times the value in the underline digit in 36,119,432 (#that is underline is number 1 between the 1 and 9 )

I think the answer is one hundred thousand

#2) which digit is 1/1000 of the value in the underline digit in 19,832,456 (# underline is 3)

My answer 30thousand

Just add a 0 when multiplying by 10.

#1) 100,000.
The number already is 30,000.
#2) 30

I would highly recommend cymath . com