Answer:
Answer: 
 
The number of chirps per minute is 72 
 
Step-by-step explanation: 
 
Here, using the formula given, we want to find the number N representing the number of chirps per minute. 
 
To get this, we shall simply substitute the value of 58 for T in the equation; 
 
Thus; 
 
58 = 50 + (N-40)/4 
 
58 -50 = (N-40)/4 
 
8 = (N-40)/4 
 
4 * 8 = N -40 
 
32 = N -40 
 
N = 40 + 32 
 
N = 72
Explanation: