800
I think your question is asking how you would round 17.521 to the nearest number with 1 significant figure...if that's the case, it would round to 10.
700 or 650.8
2000
Well, darling, if you want to round 38562.7 to 1 significant figure, you'd end up with 40000. Yes, you heard me right, 40,000. That's just the way the cookie crumbles when it comes to significant figures.
200
Round 12 to 1 significant figure is 10.
It is 0.01
7000
0.9
0.1
10000000
9000
2,000,000
12
800
100