Math help?

woo math help!! I dont need answers, I just need a formula or a way to do the work, ill do the work I only need the guidance lol thanks!!

1.To fill a 50- liter barrel, wine and water are mixed in the ratio of 5:3 by volume. Ho much wine was used to fill the barrel?

A 7 meter wide road is constructed around a circular park and the diameter of the park is 26 meters. What is the area of the circular road?
A cone has a volume of 375 cu cm. What will be its volume of its radius if its decreased by 10%?
A bag contains 4 red marbles 6 yellow and 5 blue. Liz picks two marbles at random without replacement, Find the probability that she picks two red marbles. (I thought I knew it, but the answer came out way off)
1. Jim rolls a di 18 times. He recorded the results in the given table where x is the nuber on the di and why is the number of ties it appears. Which number has equal theoretical and experimental probability of being rolled?

x=1 2 3 4 5 6 y=1 6 5 1 3 2

thanks if you can help me I really appreciate it:]