1. 4
2. 9
3. 21
are the answers
Answer:
Step-by-step explanation:
The terms of this sum make the arithmetic sequence.
The fomula of a sum of <em>n</em> terms of an arithmetic sequence:
We have
Substitute:
Actually, she worked for seven hours, so I'll solve for that.
7.20 x 3 = 21.6
6.75 x 4 = 27
21.6 + 27 = 48.6
48.6 /2 = 24.3
Her average should be $24.3 If she did work six hours, just multiply 6.75 x 3 and do what I did.
The formula to calculate work done is -
Work done ( in joule, J) = Force (in Newton) X Distance (in meters)
So, we will use the formula to calculate work done,
Here, force is given as = 7 newtons
Distance is given as = 3 meters
So, work done will be -
Work done ( in joule, J) = 7 Newtons X 3 Meters
<u>Work done ( in joule, J) = 21 J (in joule)</u>