Earth's surface is heated unevenly by the Sun. A student wants to make a model that shows how this uneven
heating is related to the curved shape of Earth's surface. In
the model, the Sun will be represented by a bright
flashlight
Which object would best represent Earth in the student's model?
O A. A flat board tilted at an angle
B. A second flashlight
O C. A shallow tray filled with soil
D. A round beach ball

D.

Explanation:

The earth is round and when the sun is shining on the earth the light of the sun is directed to one main surface that is directly towards towards the sun. This area depending on the time of year is the equator( or the middle of the earth) the further away from equator or the surface that is receiving the most of the sun light the less sun light and heat reaches it.

d. new methods of assembly are introduced.

explanation:

this allows for the goods to be made on a larger scale. not faster because now it is shown to be made better, hence the greater productivity in the question. it is calling for something new to be introduced.