Answer:
B
Step-by-step explanation:
The study doesn't prove a causation, only a correlation. So we can conclude that cities with good air quality do not have traffic jams.
Answer:
4 or -4
Step-by-step explanation:
Y is directly proportional to x^2 means there is a constant, k, such that y=kx^2.
We are given y=8 when x=2. This information will allow us to find k in the equation y=kx^2.
8=k(2)^2
8=k(4)
This implies k=2 since 2(4)=8.
So the equation for any pair (x,y) is y=2x^2.
We want to find x when y=32.
32=2x^2
32/2=2x^2/2
16=x^2
This implies x=4 or -4.
Answer:
15
Step-by-step explanation:
From the frequency table
70 - 79 → 5
80 - 89 → 6
90 - 100 → 4
Students scoring 70 or better = 5 + 6 + 4 = 15
