4. What are the basic scientific principles the engineers who designed the digital scales would have needed to understand to design this tool? Circle the correct answer(s).
A. electric currents
B. physical properties of metals
C. influence of gravitational force on objects
D. physical and chemical properties of materials used in building circuits
Houghton Mifflin Harcourt

i would think it's food chain

does anyone know or what?

c because the news are a source of information of things that happen on the daily and shows evidence about that particular topic

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.