The graph of the function
is
- concave upward, when

- concave downward, when

Find 
1.

2.

Now:
1. when
the graph of the function is concave upward and this is for

2. when
the graph of the function is concave downward and this is for

Probably the last one
Use the equation for the area of a triangle 1/2(bxh)
Then multiply that number by 2 to get the area of the complete shape.
Answer:
6 6/7 km/h
Step-by-step explanation:
The relations between speed, time, and distance are ...
time = distance/speed
speed = distance/time
__
So, to find the average speed, we need to know the total distance and the total time. The distances are given, but we need to compute the times.
time jogging = (2 km)/(8 km/h) = 1/4 h
time walking = (2 km)/(6 km/h) = 1/3 h
Then the woman's average speed is ...
average speed = (total distance)/(total time) = (2 km + 2 km)/(1/4 h + 1/3 h)
= (4 km)/(7/12 h) = 48/7 km/h
= 6 6/7 km/h
C. we multiply the equation by 3