Part A)
His sample only involves days during the summer (if Devin is in the northern hemisphere), which would mean that the high temperatures he'll record are likely to be higher than the average. Therefore, the sample mean he computes does not represent the average high temperature for the whole year.
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Part B)
To correct his mistake, he needs to sample every day of the year. Or he could sample a few days of each month (say the first ten days of each month). That way the entire year is better represented. The other seasons of spring, fall and winter are included now.
Substitue y=3x into the other equation to get 3x=-x+4. Solve this to get 4x=4 therefore x=1.
knowing this, y=3
Answer:

Step-by-step explanation:
Step 1: Identity the radius.
Since O is the center of the circle, and C and E lie on the circumference, OC and OE are the radii of the circle and thus,
OC=OE.
Step 2: Consider the rectangle.
All diagonals in a rectangle are congruent so this means
DB= OC ( OC is also a diagonal).
Thus, OC= 10 units.
Step 3: Analyze
So this means OE is also 10 units as well.
Since we know the length of the radius, Use the area of circle,


So the area of a circle is 100 pi.
The constant proportionality is 2/3 because it will still be going on
for example- 2/3+2/3= 2/3*2
The number 2/3 goes