Okay. If a car takes 2 hours to go 80 miles, the car is going 40 miles an hour. All you have to do is 80/2 in order to get your answer, because you do distance divided by time to find the speed.
Answer:
The object is most likely to be a (distant) galaxy
Explanation:
Distance of galaxies are often calculated based on the unit of light year.
The abbreviation, mpc which translates to mega parsec
A mega parsec is equivalent to 3.3 light years.
So, if the astronomer sighted the object from a distance of 28mpc which is equivalent to 28 * 3.3 light-years (92.4 light years); the object is most likely to be a galaxy; a distant galaxy
The speed of sound in a solid would be 6000 metres per second
The guy below is wrong!
F=ma
Where force = mass x acceleration
We dont have acceleration, a= change in velocity divided by the time taken.
a = v (final velocity) - u (initial) / t
a us 8-0 (at rest means u was 0) / 20 = 0.4
Using F=ma
F= mass x acceleration
F= 4 x 0.4
F=1.6 N
The layers of the fossil the oldest is usual the bottom layer,and the top layer is the newest layer