The second one is the function
Answer:
The correct option is b.
Step-by-step explanation:
The formula for standard deviation is
where, 
is mean of the data and n is number of observation.
The variance of a stock's returns can be calculated by the above formula.
Variance of stock's returns is the average value of squared deviations from the mean.
Therefore the correct option is b.
Answer:
Step-by-step explanation:
1,8
5,7
2,3
Answer:
formula: y-y1 = m(x-x1)
Step-by-step explanation:
General:
1. find 2 points directly on the line and apply the formula y2-y1 over x2-x1 this answer equals m
2. then add it into the formula y-y1 = m(x-x1) remember x and y are variables so only put numbers in y1 and x1
3. solve the problem
Example:
line 1:
1. y2-y1 over x2-x1 is 4-6 over 6-4 = -1
2. y-6 = -1(x-(-4) or y-6 = -1(x+4)
3. y-6 = -1x-4
4. y = -1x-2
3. the gradient equals: y = -1x-2
Hope this helps :) Let me know if you need a better example
