Answer:

Explanation:
v = Orbital speed = 130 km/s
d = Diameter = 16 ly
r = Radius = 
G = Gravitational constant = 6.67 × 10⁻¹¹ m³/kgs²

As the centripetal force balances the gravitational energy we have the following relation

Mass of the the massive object at the center of the Milky Way galaxy is 
The pressure at the bottom of a column of fluid in a container
depends only on the depth of the fluid, not on the shape of the
container. The pressure is simply the result of the weight of the
fluid resting on the bottom.
Answer:
or

Explanation:
We know that Gauss's law states that the Flux enclosed by a Gaussian surface is given by

Here , E is electric field and S is surface are and q is charge enclosed by the surface and e is electrical permeability of the medium.
Here the Gaussian is of radius r<R so area of surface is

Also, charge enclosed by the surface is

therefore,

Here Q is total charge,
Insert values in Gauss's law

Rearrange them

on further solving

This is the required form.