An object is thrown horizontally from the open
window of a building. If the initial speed of the
object is 20 m/s and it hits the ground 2.0 s later,
from what height was it thrown? (Neglect air
resistance and assume the ground is level.)
Initial vertical velocity = 0
formula: s = ut + (1/2)*g*t^2
s = 0 + 1/2*9.8*2^2
s = 9.8*2 = 19.6 m
Answer: 1 000 times
Explanation: 1 000 centimetre is equal to 1 dekacemetre.
Using conversion will apply in converting every number.
The problem is basically asking us to find a way to find the sound intensity I, in terms dependent on the sound level and the reference intensity 
.For this purpose we can start from the unit used in the scale logarithmic decibel, that is
Where
I = Acoustic intensity on the linear scale
Hearing threshold
Using the logarithmic properties of the exponents the above expression can be described as:
that is the expression or technique to find the intensity of sound.
There are only two types of planetary motion and these kinds are revolution and rotation. Revolution is the act of the planets in the solar system to move around or "revolve" around the sun while rotation is done in which the planet "rotates" on its axis. In addition, the earth revolves around the sun in 365 and 1/4 days.
