Answer:
a)
, b)
, c)
.
Explanation:
a) Let assume that car travel on a horizontal surface. The equations of equilibrium of the car are:


After some algebraic handling, the following expression for the propulsion force is constructed:



b) The power require to move the car at a speed of 5 meters per second is:



c) The efficiency of the car is:


Answer:
Sub stratul exterior lichid-metal al miezului Pământului se află o bilă solidă de fier și aliaj de nichel cu aproximativ 1,60 km în diametru.
Explanation:
Atmosphere - gas
sea and oceans - liquid and solid
land -liquid and solid
living things and plants - liquid
The answer is Strontium(Sr)