Indicate valleys, hills, steepness and gentleness of slopes.
Answer:
The basic purpose for which most simple machines are designed is to reduce the effort (force) required to perform a simple task. To achieve this, the force applied must act over a longer distance or period of time resulting in the same amount of work being performed by a smaller force.
Answer:
aerodynamics
Explanation:
if an object like a car is going 200 mph at max speed and then the car gets aerodynamic or smoothed to the point that air can get by the car it could end up going another 20 mph faster
DE = DC + CE
27 = 3v - 30 + 6v - 15
27 = 9v - 45
v = 8