There are a total of 5+8+2=15 marbles. There's a 5/15 chance of drawing a red marble in the first trial. Then, there are 4 red marbles and 14 total marbles left, so afterwards, there's a probability of 4/14 that the second marble is red. The probability overall is found by multiplying these together, so the first answer is the best.
There are 2+6+7=15 cakes. There's a 6/15 chance that the first cake selected will be a pineapple cake, and then a 2/14 chance that the second cake selected will be a strawberry cake, by the same logic as above. This is equal to 12/210. The first answer is the best option.
The answer would be 65°. This is because 180° -50° equals 130°. And 130° divided by two equals 65°. The two remaining angles must be equal because it is an isosceles triangle.