If a scientist is studying a model that is a widely accepted theory about the position of planets and sun, the model would most likely help the scientist to understand facts that can't be easily observed. That will make the correct answer to be C.
Answer:
To summarize and analyze data with both a crosstabulation and charting, Excel typically pair PivotCharts with PivotTables (option b)
Explanation:
Pivot Tables allows us to deal with a high volume of data. This kind of tables are mainly designed to summarize, analyze and explore data in a simple way. Meanwhile, Pivot Charts gives the possibility to visualize the summarizing data provided in PivotTables, enabling the detection of trends, correlations,comparisons and so on. Because of that Pivot tables and pivot charts are usefull and complementary tools of Excel.
Summarizing, the proper option is b.
Answer:
For the bird moving in a straight line, the kinetic energy is one-half the product of the mass and the square of the speed: Ek=12mu2.
Answer:
a. 
b.
Explanation:
#Apply surface charge density, electric field, and Gauss law to solve:
a. Surface charge density is defined as charge per area denoted as 
, and the strength of the electric field outside the sphere 
Using Gauss Law, total electric flux out of a closed surface is equal to the total charge enclosed divided by the permittivity.
#surface charge outside sphere.

Hence, the new charge density on the outside of the sphere is 
b. The strength of the electric field just outside the sphere is calculated as:
From a above, we know the new surface charge to be
,

Hence, the strength of the electric field just outside the sphere is 
Answer:
81.8 m/s
Explanation:
The initial velocity of the plane is:
(toward east)
So, decomposing along the x- and y- directions:

(we took east as positive x-direction and north as positive y-direction)
The acceleration is
(northwest, so the angle with the positive x-direction is 135 degrees)
Decomposing it along the two directions:

So the two components of the velocity after a time t = 25.0 s will be

So, the magnitude of the velocity of the plane will be
