Answer:
The amount of time for the whole journey is 8 hours.
Explanation:
A truck covered 2/7 of a journey at an average speed of 40 mph. Representing 1 the total of the trip traveled, then the rest of the distance traveled is calculated as: 
So if the truck covered the remaining 200 miles at
, this means that
of the trip represents the 200 miles. So, to calculate the total distance traveled by the truck, you apply the following rule of three: if
of the route represents 200 miles, the integer 1 (which represents the total of the route), how many miles are they?

miles= 280
So the total distance traveled is 280 miles. Since speed is the relationship between the space traveled by an object and the time used for it (
), then if the average of the entire trip was 35 mph and the distance traveled 280 miles, the time is calculated as:

time= 8 h
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The amount of time for the whole journey is 8 hours.</em></u>
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Answer:
532 millimeters of mercury
Explanation:
In order to convert the pressure from atm to millimeters of mercury (mm Hg), we should remind the conversion factor between the two units:
1 atm = 760 mm Hg
Therefore, we can solve the problem by setting up the following proportion:

Solving for x, we find

Answer: the photograph will likely show only one star.
Explanation:
Since their angular separation is smaller than the telescope's angular resolution, the picture will apparently show only one star rather than two.
The doppler effect is the increase or decrease in the frequency of sound, light, or other waves as the source and observer move toward or away from each other.