Answer:
A. The closest point in the Moon's orbit to Earth
Explanation:
The perigee is defined as the closest point in the orbit of an object (such as a satellite) from the centre of the Earth. In this case, the Earth's satellite is the Moon, so the perigee is defined as the closest point in the Moon's orbit to Earth. so option A is the correct one.
Let's see instead the names of the other options:
B. The farthest point in the Moon's orbit to Earth --> this point is called apogee
C. The closest point in Earth's orbit of the Sun --> this point is called perihelion
D. The Sun's orbit that is closest to the Moon --> this point has no specific name
Displacement is a vector magnitude that depends on the position of the body which is individualistic for the trajectory.
While, Distance is a scalar magnitude that measures over the trajectory.
Answer: proton mass 1 and neutron has no mass number
Explanation: proton because of positive charge neutron because of negative charge
Expensive: Hydrogen gas actually takes a considerable measure of work to free if from different components. If it were basic and simple to separate, everybody would be utilizing it. It’s now being utilized to power some hybrid vehicles, yet right now it is not a reasonable type of fuel for everybody, mainly because it’s pricey and it’s difficult to get it from place to place. Until research and innovation goes far enough to make this a simpler and cheaper task, hydrogen will likely be something that only the rich can afford.Not Enough Hydrogen Fuel Stations: As you likely know, it’s very difficult to change “the way things are.” As difficult as hydrogen is to create and transport, it gets to be considerably pricier when you consider attempting to utilize it to supplant fuel. There is no current framework set up to hydrogen as the primary fuel for the normal driver. Service stations and vehicles themselves would all must be changed in order to use hydrogen, which can take a lot of time and money to do. It doesn’t seem cost efficient to change from the norm.Safety Concerns: Hydrogen in itself has a lot of power behind it. Though it is less dangerous than gasoline, it’s profoundly flammable and constantly in the news for the potential dangers connected with it. Unlike gas, hydrogen has no smell. Sensors must be used to detect a leak.
