Concept: 
Frequency- It is defined as the number of oscillations occur in one second. 
Its SI unit is Hertz (Hz)
Given: Produced sound vibrations is 18,500 cycles in 0.75 seconds
∵ In 0.75 second, produced sound has oscillations = 18,500 cycles
∴ In 1.0 second, produced sound has oscillations = (18,500 ÷ 0.75) Hz
The frequency of the sound will be ≈ 24,667 Hz
From the study of the given graph, only the animals (c) Cats, (b) Moths and (a) Bats can hear the produced sound because their upper audible frequency range is greater than 24,667 Hz. 
 
        
                    
             
        
        
        
Answer:
-2040 m/s²
Explanation:
Taking toward the wall to be positive, the initial velocity is 10.1 m/s and the final velocity is -8.3426 m/s.
Average acceleration is the change in velocity over change in time.
a = Δv / Δt
a = (-8.3426 m/s − 10.1 m/s) / 0.00905 s
a = -2040 m/s²
 
        
             
        
        
        
C.
The range of temperatures on Earth allows water to exist in all of its states.
        
             
        
        
        
Answer:
0.002 m or 2 mm
Explanation:
Given that:
Force, F = 50N
Area = 1 * 10^-5
Length, L = 10m
Shear modulus, = 2.5 * 10^10
Using the relation ;
D = (50 ÷ 1*10^-5) ÷ (2.5 * 10^10 ÷ 10)
D = 5000000 ÷ 2.5 * 10^9
D = 5 * 10^6 ÷ 2.5 * 10^9
D = (5/2.5) * 10^(6-9)
D = 2 * 10^-3
D = 0.002 m
1m = 1000 mm
0.002m = (1000 * 0.002) = 2 mm