The correct answer is D. An average city
Explanation:
A neutron star differs from others due to its massive density, this means a lot of matter is compressed in a small area. Indeed, neutron stars have a mass of around 1.4 to 2.8 times the mass of the sun. But these are considerably small as they only measure around 20 kilometers, which is the size of an average city. Additionally, neutron stars are this dense because they are the result of a regular star exploding, which leads to a super-dense core, or neutron star. In this context, the mass of a neutron star is compressed to the size of an average city.
The speed of an object in a set direction is its velocity.
To calculate the initial velocity of the bike, we use the following equation
.
or
Here, u is initial velocity, v is final velocity, t is the time and d is the distance covered by bike.
Given, 
,
and 
.
Substituting these values in above equation, we get
.
Thus, the initial velocity of the bike is 1.2 m/s.
Answer: 0.790 g/cm3
Explanation:
The density of acetone is 790 Kg/m3.
To convert from Kg to g we multiply by 1000 (1 Kg = 1000 g)
To convert from m3 to cm3 we multiply by 10∧6
So, The density of acetone in (g/cm3) = (790 x 1000) / (10∧6) = 0.79 g/cm3
