A and B are the correct answer for this
Answer:
t=4.86s
Explanation:
To find the wavelength you use the following formula:

v: speed of sound = 343m/s
f: frequency = 400Hz
λ: wavelength of the sound
By doing λ the subject of the formula and replacing the values of f and v you obtain:

Now, to calculate the time that sound takes to reach the last row you use:

t: time
d: distance to the last row = 1947m

hence, the time is 4.86s
Mass in physics is in kg and mass in chemistry is in grams. Therefore a person's mass is kg
Answer:
32 °C.
Explanation:
Hola.
En este caso, debemos entender que la relación entre el calor y la temperatura viene dada por:

De este modo, dado que estamos estudiando la misma sustancia (agua) con masa constante, la relación calor-temperatura es lineal y directamente proporcional, por tal razón, si se duplica el calor suministrado, la temperatura también será duplicada, de modo que:

¡Saludos!
Answer:
1

2
The distance is
Explanation:
From the question we are told that
The maximum speed of the cheetah is 
The maximum of gazelle is 
The distance ahead is 
Let
denote the time which the cheetah catches the gazelle
Gnerally the equation representing the distance the cheetah needs to move in order to catch the gazelle is

=> 
=> 
=> 
Now at t = 7.5 s

=> 
=> 
=>
Hence the for the gazelle to escape the cheetah it must be 55.2 m