Explanation:
The velocity of sound depends on the density of the medium. So we need to find the density of air at each set of conditions. The density of air is:
ρ = (Pd / (Rd T)) + (Pv / (Rv T))
where Pd and Pv are the partial pressures of dry air and water vapor,
Rd and Rv are the specific gas constants of dry air and water vapor,
and T is the absolute temperature.
At the first condition:
Pv = 31.7 mmHg = 4226.3 Pa
Pd = 650 mmHg - 31.7 mmHg = 618.3 mmHg = 82433 Pa
Rv = 461.52 J/kg/K
Rd = 287.00 J/kg/K
T = 30°C = 303.15°C
ρ = (82433 / 287.00 / 303.15) + (4226.3 / 461.52 / 303.15)
ρ = 0.94746 + 0.03021
ρ = 0.97767 kg/m³
At the second condition:
Pv = 0 Pa
Pd = 650 mmHg = 86660 Pa
Rv = 461.52 J/kg/K
Rd = 287.00 J/kg/K
T = 0°C = 273.15°C
ρ = (86660 / 287.00 / 273.15) + (0 / 461.52 / 273.15)
ρ = 1.1054 + 0
ρ = 1.1054 kg/m³
The square of the velocity of sound is proportional to the ratio between pressure and density:
v² = k P / ρ
Since the atmospheric pressure is constant, we can say it's proportional to just the density:
v² = k / ρ
Using the first condition to find the coefficient:
(340)² = k / 0.97767
k = 113018.652
Now finding the velocity of sound at the second condition:
v² = 113018.652 / 1.1054
v = 319.75
Answer: spectroscopy
Spectroscopy is the separation of the light in the different wavelengths and spectrophotometry measures the intensities of the different components of the light to get the composition of substances.
Answer:

34.46 V/m
Explanation:
= Vacuum permeability = 
c = Speed of light = 
I = Intensity = 1.575 W/m²
The maximum magnetic field intensity is given by

The magnetic field intensity is 
The maximum electric field intensity is given by

The electric field intensity is 34.46 V/m
Answer: Plant A
Explanation: The control group is participants who do not receive the experimental treatment.
Answer:
1)a. It is constant the whole time the ball is in free-fall.
2)b. = 14 m/s
3) e. = 19.6 m/s
Explanation:
1) given that the only force acting on the ball is gravity, gravity acts along the vertical axis. Since no other force acts on the ball then the horizontal velocity will remain constant all through the flight since there is no horizontal force acting on the ball.
2) speed = distance/time
horizontal distance = 56m
Time = 4 seconds
Speed = 56m/4s = 14m/s
3) acceleration due to gravity g = 9.8m/s^2
Initial vertical velocity = u
Final vertical velocity = v = -u
Using the law of motion;
v = u + at
a = acceleration = -g = -9.8m/s^2
t = time of flight = 4
Substituting the values;
-u = u - 4(9.8)
-2u = -4(9.8)
u = -4(9.8)/-2
u = 2(9.8) = 19.6 m/s
Initial vertical velocity = u = 19.6 m/s