Answer:
The parametrization, of the given curve is 
Step-by-step explanation:
From the question we are given the function

At y= 5


Converting the above to it polar equation we have

Answer:
c
Step-by-step explanation:
A line that rises from left to right has a positive slope.
That is a 45 degree angle on the side
Answer:
4 mph
Step-by-step explanation:
The average speed of an object is given by the total distance covered by the time taken:

where
d is the total distance covered
t is the time taken
in the first part, the person runs for 0.4 hours at a speed of 7 mph, so the distance covered in the 1st part is

Then the distance covered in the second part is
, so the total distance is
(1)
The total time elapsed is 0.4 hours (first part) + 0.8 hours (second part), so

So we can write the average speed as
(1)
We want the average speed to be 5 mph,
v = 5 mph
Therefore we can rearrange eq.(1) to find d2:

And therefore, the speed in the second part must be

5a - 10*3 = 45
5a - 30 = 45
5a = 45 + 30
5a = 75
a = 15