Can someone show me how to do 18 and 19 like with work too

Part a: select all of the ordered pairs that are located on the graph of the equation. part b: does the graph of the equation represent a function? select all correct answers for part a and one answer for part b.

The size of a certain cell is 2.5*10^-9m. another cell is 1.5*10^3 times larger. how large is the larger cell in scientific notation?

If angle 2=3x +1 and angle 3=2x +4what is angle 2