Two opposite rays
form
a line.
never
sometimes
always

always.

Step-by-step explanation:

A ray has a starting point but no end point. Therefore if 2 opposite rays are connected at their endpoints, a line is formed. I cannot think of an exception to this because the definition of a ray is very rigid (the end point is always included).

whole numbers.

step-by-step explanation:

we are given the average monthly rainfall (in millimeters) model r(m) for the years 1900-2009 as a function of the month number m.

as we can see m is taken for the number of months for years 1900-2009.

we know that number of months can't be a negative number or decimal number or a fraction.

so, the number of months could be only positive whole numbers.

therefore, whole numbers is more appropriate for the domain of r.

3

step-by-step explanation: