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
Answer:
You were a freeloader of my questions, so I'll be one too.
Answer:No, it doesn't move easily downward because it will try to resist the movement ,due to a resistance force of inertia that it possess at rest.
Explanation:when an object has higher or larger mass it tends to resist any motion given to it unlike the one with lower mass.
The larger the mass the more resistance force an object has.
They have some but not very much, the particles in the ice are still vibrating just not as much as in water. the only time a substance would have 0 kinetic energy is when that substance is at 0 degrees kelvin(absolute zero) so far no place in the universe has been recorded at absolute zero though