There are 35 people in Annie's class, which means, she has 35 - 1 = <<35-1=34>>34 classmates.
Every classmate got 2 candies, so in total Annie gave out 34 * 2 = <<34*2=68>>68 candies.
In the beginning she had 68 + 12 = <<68+12=80>>80 candies.
One candy costs $0.1, so Annie spend 80 * 0.1 = $<<80*0.1=8>>8 on candies.
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