I bealive it is b. ( I had the exact same 7 th grade homework page ad u today;)
The radius can be found with the Pythagorean theorem. Assuming r is the radius, 14²+r²=17². Multiply it out to 196+r²=289. Subtract 196 from both sides and you're left with r²=93. So, r=√93, or about 9.6 to the nearest tenth.
If the probability of her having the winning ticket is 1., which equals 100%, then that means she bought all the tickets, so 1000 tickets
