For each of the following (a through d), indicate which is a variable and which is a constant:a. The number of minutes in an hour. b. Systolic blood pressure. c. Freezing temperature of water in degrees Kelvin. d. Ratings of daily anxiety.

The number of minutes in an hour - constant

Systolic blood pressure - variable

Freezing temperature of water in degrees Kelvin - constant

Ratings of daily anxiety - variable

Explanation:

A variable speaks of something that change while a constant is something that doesn't change.

The number of minutes in an hour is always constant which is 60.

Systolic blood pressure refers to the amount of pressure in your arteries during the contraction of your heart muscle and this changes base on the work done by the heart thus will be a variable.

Freezing temperature of water in degrees kelvin is always constant and it is 273.2 K.

Ratings of daily anxiety will be a variable because daily anxiety differs for different challenges of life.