the answer is c) the speed and direction of travel must be constant
Letter na that would be the answer
To solve this problem we need to apply the corresponding sound intensity measured from the logarithmic scale. Since in the range of intensities that the human ear can detect without pain there are large differences in the number of figures used on a linear scale, it is usual to use a logarithmic scale. The unit most used in the logarithmic scale is the decibel yes described as

Where,
I = Acoustic intensity in linear scale
= Hearing threshold
The value in decibels is 17dB, then

Using properties of logarithms we have,




Therefore the factor that the intensity of the sound was 
Answer:
a) When the sides of the joint are close together, the particles have more kinetic energy than they do when sides are farther apart.
Explanation:
Answer:
When deformed, it returns to its original shape
Explanation:
- A spring is elastic.
- Elasticity is the property of a material to regain its shape after having been deformed.
- It means that when the force is doubled, the amount of deformation in it gets doubled.
- Hence, the correct option is (b) " When deformed, it returns to its original shape".