Which statement must be true? a cube can have a cross section that is a triangle. a sphere can have a rectangle as a cross section. a cone can have a cross section that is a square. a cylinder can have a cross section that is a sphere.

yes because there is exactly one y value for every x value

for function there can't be more than one value for every x value

-3.5 degrees per hour

step-by-step explanation:

find the unit rate:

-12   1/4 degrees           12.25 degrees

= - = -3.5 degrees per hour

      3   1/2 hours               3.5 hours