A mathematical demand function for new Toyotas sold per year for a dealer is as follows

Qr = 200 - 0.001Pt + 0.005Pm - 10Pg + 0.01I +0.003A

where 

                Qt = quantity purchased,

                Pt = the average price of Toyotas,

                Pm = the average price of mazdas,

                Pg = the price of gasoline,

                I = per capita income, and

                A = dollars spent annually on advertising

1. Characterize this function by circling all in the following list that are applicable:

univariate, bivariate, multivariate, linear, exponential, logarithmic, curvilinear, 1st degree, 3rd degree, additive, multiplicative, linearly homogeneous

2. What is the numerical value of the partial derivative of the function with respect to advertising spending (be sure to also include the + or – sign, but I do not want the symbol for this)?

3. Write the mathematical symbol representing the coefficient of the price of gas (the numerical value of this coefficient is -10, but the answer you give is to be the symbol for this partial derivative).

4. Assuming there is a $1 increase in the price of gasoline, what change in Toyota demand will result (give the numerical value, too)?

5. Are Mazadas a substitute for or complementary to Toyotas? What feature of the function tells you?

6. Explain in words what the intercept (which is 200) includes (or does not include).

7. The sign of the variable I is +. Suppose it were negative (that is -.01). What would the negative sign tell you about the type of good Toyotas are?

8. Glory be! Enough pipe lines have finally been constructed to carry significantly more oil from the Cushing, OK, petroleum exchange to refineries in Houston. As a result, the price of gasoline decreases by $2.00 per gallon. What change in Toyoto demand will result (give the numerical value, too)?

9. The amount budgeted for advertising spending is cut by $100,000. What change in Toyoto demand will result (give the numerical value, too)?

10. Which will cause a greater influence on Toyota demand: a $1,000 decrease in the price of a Toyota or a $1000 increase in the price of a Mazada? Explain what items in the given function give you this information.