Answer:
The family in the first period is the alkali metal family.
Answer:
<u><em>When sunlight shines through an orange solution, the violet, blue and green wavelengths are absorbed.</em></u> The other colors pass through.
By building dams and levees . Hope this helps
Answer:
Explanation:
Length if the bar is 1m=100cm
The tip of the bar serves as fulcrum
A force of 20N (upward) is applied at the tip of the other end. Then, the force is 100cm from the fulcrum
The crate lid is 2cm from the fulcrum, let the force (downward) acting on the crate be F.
Using moment
Sum of the moments of all forces about any point in the plane must be zero.
Let take moment about the fulcrum
100×20-F×2=0
2000-2F=0
2F=2000
Then, F=1000N
The force acting in the crate lid is 1000N
Option D is correct
It occurs when energy is supplied or withdrawn :)