Which of the following situations forms a proportional relationship? Select all that apply. 5 DVDs for $9 and 15 DVDs for $27

6 cups of coffee for $8 and 9 cups of coffee for $12.

3 purses for $60 and 5 purses for $90

12 cans of soup for $3 and 30 cans for $7.50.

2 ink cartridges for $25 and 4 ink cartridges for $75.

Arefrigeration system at your company uses temperature sensors fixed to read celsius (°c) values, but the system operators in your control room understand only the fahrenheit scale. you have been asked to make a fahrenheit (°f) label for the high temperature alarm, which is set to ring whenever the system temperature rises above –10°c. what fahrenheit value should you write on the label?