# data[].attributes.headline
function that contains a constant interval

# data[].attributes.subject
function that contains a constant interval

# data[].attributes.headline
function that contains a decreasing interval 

# data[].attributes.subject
function that contains a decreasing interval 

# data[].attributes.headline
function that contains an increasing interval

# data[].attributes.subject
function that contains an increasing interval

# data[].attributes.headline
function with a range of all positive real numbers and zero 

# data[].attributes.subject
function with a range of all positive real numbers and zero 

# data[].attributes.headline
function with a domain of all real numbers 

# data[].attributes.subject
function with a domain of all real numbers 