On a certain fall day in Anchorage, Alaska, the temperature at 1:00 a. m. was −1.6°C. At 1:00 p. m. (12 hours later), the temperature had risen to 3.2°C. On average, how much did the temperature change, in degrees, each hour from 1:00 a. m. to 1:00 p. m.? A. −1.6° per hour B. −0.4° per hour C. 0.4° per hour D.1.6° per hour

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional