Answer:
a) 910
b) 828100
c) 144320
Step-by-step explanation:
a. ∑y
This is the sum of all values of y. So

b. (∑y)^2
This is the square of the sum, so the square of 910, that we found in the previous item.
910² = 828100
c. ∑y^2
This is the sum of the squares of each amount spent. So

Vicky’s average speed is 0.55m/h
Answer:

Since the angle between the two vectors is not 180 or 0 degrees we can conclude that are not parallel
And the anfle is approximately 
Step-by-step explanation:
For this case first we need to calculate the dot product of the vectors, and after this if the dot product is not equal to 0 we can calculate the angle between the two vectors in order to see if there are parallel or not.
a=[1,2,-2], b=[4,0,-3,]
The dot product on this case is:

Since the dot product is not equal to zero then the two vectors are not orthogonal.
Now we can calculate the magnitude of each vector like this:


And finally we can calculate the angle between the vectors like this:

And the angle is given by:

If we replace we got:

Since the angle between the two vectors is not 180 or 0 degrees we can conclude that are not parallel
And the anfle is approximately 
Answer: the answer is c
Step-by-step explanation:
your welcome