For this case we have the following equation:
w = || F || • || PQ || costheta
Where,
|| F ||: force vector module
|| PQ ||: distance module
costheta: cosine of the angle between the force vector and the distance vector.
Substituting values:
w = (60) * (100) * (cos (45))
w = 4242.640687 lb.ft
Answer:
The work done pushing the lawn mower is:
w = 4242.640687 lb.ft
K is the slope of the line formed by connecting the points.
Use slope formula:

where the 2 points are the end points of the line (First and last going Left to right)

Substitute into slope formula

You can check if this is correct by going back to graph and going "up 7" and "over 2" to get from one point to the next.
Since it is under 985,000, you would round it down. So your answer rounded to the nearest ten thousand would be 980,000