1. <span>Molecules rearrange and form new molecules - exchange (they exchange some material in order to produce new things)
2. </span><span>simultaneous decomposition and synthesis - reversible (it can go back)
3. </span><span>bonds broken and elements released - decomposition
4. </span><span>molecules formed from components - synthesis (these components merge and create molecules)</span>
Answer-A
The water cycle shows how water moves around earth.
Ex: Runoffs,precipitation, condensation, evaporation.
-Steel jelly
Answer:Friction is a force that opposes the motion of objects; friction can cause objects to slow down. Air resistance is a type of friction. Air resistance causes moving objects to slow down. Different physical properties, such as the shape of an object, affect the air resistance on an object.
Explanation:
To develop this problem it is necessary to apply the oscillation frequency-related concepts specifically in string or pipe close at both ends or open at both ends.
By definition the oscillation frequency is defined as

Where
v = speed of sound
L = Length of the pipe
n = any integer which represent the number of repetition of the spectrum (n)1,2,3...)(Number of harmonic)
Re-arrange to find L,

The radius between the two frequencies would be 4 to 5,


Therefore the frequencies are in the ratio of natural numbers. That is

Here f represents the fundamental frequency.
Now using the expression to calculate the Length we have

Therefore the length of the pipe is 1.3m
For the second harmonic n=2, then

Therefore the length of the pipe in the second harmonic is 2.6m