Potassium is the 19th element so it is B
Answer:

Explanation:
<u>Average Acceleration
</u>
Acceleration is a physical magnitude defined as the change of velocity over time. When we have experimental data, we can compute it by calculating the slope of the line in velocity vs time graph.
Note: <em>We cannot see if the time axis is numbered in increments of 1 second, and we'll assume that.
</em>
When
, the graph shows a value of
When
, the object is at rest, 
We compute the average acceleration as




Biological weathering is weathering caused by plants and animals. Plants and animals release acid forming chemicals that cause weathering and also contribute to the breaking down of rocks and landforms. Chemical weathering is weathering caused by breaking down of rocks and landforms.
I am pretty sure about these answers.Thermal goes in the 4th blank.
Mechanical goes in the 2nd blank.
Electrical goes in the 3rd blank.
I think chemical goes in the 1st blank and light goes in the 5th blank
Hope this helps
Answer:
Explanation:
For time period of revolution , the expression is as follows .
T² = 4π² R³ /GM , M is mass of the earth.
Putting the values
T² = 4π² (7880 x 10³)³ /(6.67 x 10⁻¹¹ )( 5.97 x 10²⁴ )
T² = 4.846 x 10⁷ s
T = 6.961 x 10³ s
= 6961 s
= 116 minutes .