To get x on its own, you times the 3 over to the other side so the 3 cancels out on the LHS.
~ x greater than or equal to -18
(C)
Answer:
Explanation:
Given
Lowest four resonance frequencies are given with magnitude
50,100,150 and 200 Hz
The frequency of vibrating string is given by

where n=1,2,3 or ...n
L=Length of string
T=Tension
Mass per unit length
When string is clamped at mid-point
Effecting length becomes 
Thus new Frequency becomes

i.e. New frequency is double of old
so new lowest four resonant frequencies are 100,200,300 and 400 Hz
The Electromagnetic ave that is about the size of humans is : A typical micro waves have around 14 inches ( 1.1 meter) in height.
This is very similar to the height of human right before we hit puberty (around 9 - 10 years old)
You can only determine the speed since the only info we know is how much you ran in how long of a time.
Because a lot of people live along the fault line and there would be lots of death and much property damage.