Question 1093530
19 bottles
probability of Fanta for first is 4/19 * probability of Fanta for second which is 3/18.  Joint probability is 12/342 or 2/57.
Sandra picked Fanta (4/19)*(15/18), assuming that Sandra picks first. This is 60/342 or 10/57.
Same brand is Fanta (above) which is also 12/342; coke, which is 9/19*8/18=72/342; pepsi, which is 6/19*5/18 or 30/342.  The sum is 114/342 or 1/3.
If they picked different brands, that would be 2/3, since it is dichotomous, meaning one or the other.