Answer: City A, 
Step-by-step explanation:
Given
The temperature of city A is 
The temperature of city B is 
We know, 
So, 

Clearly, the average temperature of city A is more than city B
The difference in temperature is 
Answer:

Step-by-step explanation:
Let the variable be 'x'.
- Sum of 3 and x = x + 3
- 4 times the sum of 3 and x = 4 (x + 3)
Expression : 4 (x + 3)
On expanding ,
4 (x + 3)
= (4*x) + (4*3)
= 4x + 12 ⟶ equivalent expression to the statement .

You have to use Pythagorean’s theory
Let f(x) represents the heart beat of the person.
Now, we have been given that person’s theoretical maximum heart rate is given by 220 - x.
Also, we have been given that person strive for a heart rate that is at least 50% of the maximum. At least means greater than equal to.
Thus, we have

Also, we have been given that person strive for a heart rate that is at most 75% of the maximum. At most means less than equal to.
Therefore, the system of inequality is given by

<span>The square mile (abbreviated as sq mi and sometimes as mi2) is an imperial and US unit of measure for an area equal to the area of a squareof one statute mile. It should not be confused with miles square, which refers to the number of miles on each side squared.</span>