Answer:
a.
b.
Explanation:
We are given that




a.We have to find the angle


b. We have to find the speed 
According to law of conservation of momentum



Answer:
Mount Rushmore is a very well built sculpture. It is visited by millions of people each year to see 60-foot tall images of the American presidents; George Washington, Thomas Jefferson, Abraham Lincoln and Theodore Rosevelt which are carved into the Black Hills of South Dakota. Mount Rushmore has faced many controversies too. The land it was built on is sacred to Native Americans. The Sioux were also forced to leave the land, after lots of battles
Explanation:
Answer:
The electronic configuration of Fe2+ is 1s2 2s2 2p6 3s2 3p6 3d6 and Fe3+ is 1s2 2s2 2p6 3s2 3p6 3d5. Fe2+ contains 2 fewer electrons compared to the electronic configuration of Fe.