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:
B
Step-by-step explanation:
x is the value of x which you input into the function and f(x) is the actual function and therefore the output. so when x=3, f(x)= -2. f(3)=-2
Prime factor is a factor that is a prime number.
Prime factors of :
8 : 2 × 2 × 2. Also can be written as
12 : 2 × 2 × 3. Also can be written as
20 : 2 × 2 × 5. Also can be written as
30 : 2 × 3 × 5
56 : 2 × 2 × 2 ×7. Also can be written as
70 : 2 × 5 × 7
You can find all of them by using Factor Tree [ as shown in the picture] or Dividing by prime numbers.
The first one! It is using the distributive or associative property!
