Complete Question
The compete question is shown on the first uploaded question
Answer:
The speed is
Explanation:
From the question we are told that
The distance of separation is d = 4.00 m
The distance of the listener to the center between the speakers is I = 5.00 m
The change in the distance of the speaker is by 
The frequency of both speakers is 
Generally the distance of the listener to the first speaker is mathematically represented as
![L_1 = \sqrt{l^2 + [\frac{d}{2} ]^2}](https://tex.z-dn.net/?f=L_1%20%20%3D%20%20%5Csqrt%7Bl%5E2%20%2B%20%5B%5Cfrac%7Bd%7D%7B2%7D%20%5D%5E2%7D)
![L_1 = \sqrt{5^2 + [\frac{4}{2} ]^2}](https://tex.z-dn.net/?f=L_1%20%20%3D%20%20%5Csqrt%7B5%5E2%20%2B%20%5B%5Cfrac%7B4%7D%7B2%7D%20%5D%5E2%7D)

Generally the distance of the listener to second speaker at its new position is
![L_2 = \sqrt{l^2 + [\frac{d}{2} ]^2 + k}](https://tex.z-dn.net/?f=L_2%20%20%3D%20%20%5Csqrt%7Bl%5E2%20%2B%20%5B%5Cfrac%7Bd%7D%7B2%7D%20%5D%5E2%20%2B%20k%7D)
![L_2 = \sqrt{5^2 + [\frac{4}{2} ]^2 + 0.6}](https://tex.z-dn.net/?f=L_2%20%20%3D%20%20%5Csqrt%7B5%5E2%20%2B%20%5B%5Cfrac%7B4%7D%7B2%7D%20%5D%5E2%20%2B%200.6%7D)
Generally the path difference between the speakers is mathematically represented as

Here
is the wavelength which is mathematically represented as

=> 
=>
=>
Here n is the order of the maxima with value of n = 1 this because we are considering two adjacent waves
=>
=>
Answer:
...
<h2>PE=
<em>work done</em></h2><h2>
<em>m</em><em>gh</em><em>=</em><em>2</em><em>0</em><em>×</em><em>1</em><em>0</em><em>×</em><em>2</em><em>0</em><em>.</em><em>.</em></h2>

.
<em>I </em><em>hope</em><em> </em><em>this</em><em> </em><em>helps</em><em> </em><em>you</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em>
Answer: The formula used to solve the problems related to first law of thermodynamics is 
Explanation:
First law of thermodynamics states that the total energy of the system remains conserved. Energy can neither be destroyed, nor be created but it can only be transformed into one form to another.
Its implication is any change in the internal energy will be either due to heat energy or work energy.
Mathematically,

where, Q = heat energy
W = work energy
= Change in internal energy
Sign convention for these energies:
For Q: Heat absorbed will be positive and heat released will be negative.
For W: Work done by the system is negative and work done on the system is positive.
For
: When negative, internal energy is decreasing and when positive, internal energy is increasing.
Hence, the formula used to solve the problems related to first law of thermodynamics is 
She threw the marshmallow at a speed of around 4.76 m/s.The formula for the horizontal range gives the velocity.
<h3>What is projectile motion?</h3>
The motion of an item hurled or projected into the air, subject only to gravity's acceleration, is known as projectile motion.
The item is known as a projectile, and the course it takes is known as a trajectory. Falling object motion is a simple one-dimensional kind of projectile motion with no horizontal movement.
Given data;
The marshmallow was thrown at a distance of 2 meters
Range,R = 3 m
Initial velocity,u
The angle at which the marshmallow was thrown,θ = 30°
The acceleration due to gravity,g = 9.81 m/s²
The projectile's motion is divided into two parts: horizontal and vertical motion.

Hence, she throws the marshmallow at a speed of 4.76 m/sec.
To learn more about the projectile motion refer to the link;
brainly.com/question/11049671
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