In my opinion, i think the first one is the best one since we're cutting down on paper wasted in mails when its better to do it online.
"paying bills online instead of sending paper through mail"
Answer:
9. The Sun's Gravity
10. The core is the densest layer
Answer:
12 units
Explanation:
This problem can be solved if we take into account the equation for a sphere

where we took that the radius is 13 units. If we take z=5 and we replace this value in the equation of the sphere we have

where we have taken x2 +y2 because if the equation of a circunference.
In this case the intersection is made when we take z=5, for this value the sphere and the plane coincides in values.
Hence, the radius is 12 units
I hope this is useful for you
regards
Answer:
Convection? I'm pretty sure that's it