Use a calculator called symbolab.com
A relation is a function if each element of the domain is paired with exactly one element of the range. ... If given a table, or a set of ordered pairs, you can look to see if any value of the domain has more than one corresponding value in the range.
tbh google
1. Not random. Because you are asking people if they like ICE CREAM in a ICE CREAM shop.
2. Not random. Because they are serving a small controlled group.
3. Not random. Because you go shopping at Publix because you like it.
4. Random. Because you don't choose who is home or not.
First you find the unit rate. (Divide 2.76 by 18)
You will find out that each ounce costs $0.15
Then divide 2.07 by 0.15.
The answer is 13.8 ounces.