What is a irrational number plus a irrational number?

Which function is shown in the graph below?

Describe all the numbers that when rounded to the nearest thousand are 645,000

Atoy company is considering a cube or sphere-shaped container for packaging a new product. the height of the cube would equal the diameter of the sphere . compare the volume to surface area ratios of the containers. which packaging will be more efficient? for a sphere, sa =4πr²