In Bohr's atomic model, he proposed that the electrons are revolving around the nucleus in their respective orbitals. There are 5 kinds of orbitals: the s, p, d and f orbitals. They differ in their energy level, shape and number of subshells. Each subshell holds two oppositely spinning electrons. The s has 1 subshell, p has 3, d has 5 and f has 7. You arrange the orbitals into energy levels just like how you write them in an electronic configuration.
In the first energy level, you only have one 1s orbital. In the second energy level, you have one 2s and one 2p orbital, the 2p having more energy than 2s. The other levels are shown in the picture.
Answer:
The ladder is moving at the rate of 0.65 ft/s
Explanation:
A 16-foot ladder is leaning against a building. If the bottom of the ladder is sliding along the pavement directly away from the building at 2 feet/second. We need to find the rate at which the top of the ladder moving down when the foot of the ladder is 5 feet from the wall.
The attached figure shows whole description such that,
.........(1)

We need to find,
at x = 5 ft
Differentiating equation (1) wrt t as :



Since, 

At x = 5 ft,


So, the ladder is moving down at the rate of 0.65 ft/s. Hence, this is the required solution.
Answer:
The temperature of the mantle varies greatly, from 1000° Celsius near its boundary with the crust, to 3700° Celsius
hope this helps you!
An atom is the smallest unit of matter. It can't be broken. It consist of dense nuleus surrounded by negatively charged electrons.
The answer is true as gravity is powerful than any other force