Helpp me i don't understand constant of proportionality (don't put pictures i can't see).

You are making a battery for a science project. you have copper wire for your first electrode. you need to choose a conductor, a second electrode, and a device to plug into your battery. you have already chosen a lemon conductor. complete each statement below about the options that include a lemon conductor.

The number if marbles of different colors stored in a hat is listed below: 4 red marbles 10 green marbles 7 blue marbles. without looking in the hat, dan takes out a marble at random. he replaces the marble and then takes out another marble from the hat. what is the probability that dan takes out a blue marble in both draws?

The cost for an uberi is $2.50 plus $2.00 mile. if the total for the uber ride was $32.50, how many miles did the customer travel?