I got C for 6 & 7. I haven't done this in a while so I don't know 8 & 9. I hope I helped!
Answer:$3,700
Step-by-step explanation:
Gross sales are the total amount of sales a company earned throughout a specific period of time, without taking into consideration any costs involved with running a business. Gross sales do not factor in expenses related to running a business, also known as cost of goods sold (COGS), which get deducted when calculating net sales. For example, they do not account for costs associated with item production, employee wages, building rent, returns, theft or sales tax.
Gross Sales = $3,700
h = -4.9t^2 + vt
In our problem,
v = 12
t = 2
Let's plug our numbers into the equation.
h = -4.9(2)^2 + (12)(2)
h = -19.6 + 24
h = 4.4 m
Mean:
E[Y] = E[3X₁ + X₂]
E[Y] = 3 E[X₁] + E[X₂]
E[Y] = 3µ + µ
E[Y] = 4µ
Variance:
Var[Y] = Var[3X₁ + X₂]
Var[Y] = 3² Var[X₁] + 2 Covar[X₁, X₂] + 1² Var[X₂]
(the covariance is 0 since X₁ and X₂ are independent)
Var[Y] = 9 Var[X₁] + Var[X₂]
Var[Y] = 9σ² + σ²
Var[Y] = 10σ²