What is the regression equation?

A) calories = 5.984 + 1.072 protein +1.033 fat + 0.454 fibre +0.260 carbohydrates + 0.250 sugar
B) calories = 20.2454 + 1.072 protein +8.09 fat + 0.454 fibre +11.30 carbohydrates + 0.250 sugar
C) calories = 3.38 + 5.32 protein +8.09 fat - 2.11 fibre +11.30 carbohydrates + 13.30 sugar
D) calories = 5.984 + 5.32 protein +1.033 fat - 2.11 fibre +0.260 carbohydrates + 13.30 sugar
E) calories = 20.2454 + 5.6954 protein + 8.3596 fat - 1.0202 fibre + 2.9357 carbohydrates + 3.3185 sugar

Solve the system by the method of substitution. $$\{\begin{array}{l}{x}^2+y^2=25\\ -6x+y=5\end{array}$$

A) $(0,25),(-30,-175)$
B) $(0,5),(30,185)$
C) $(0,5),\left(-\frac{60}{37},-\frac{175}{37}\right)$
D) $(0,25),\left(-\frac{60}{37},-\frac{175}{37}\right)$
E) no solution exists

Rounded to the nearest month, how long will it take money to lose one-third of its purchasing power if the annual inflation rate is 3%?

Determine the values of a and b that satisfy the equation. $$\sqrt{-81}-7=a+bi$$

A) $a=14;b=18$
B) $a=49;b=-9$
C) $a=81;b=-7$
D) $a=-9;b=7$
E) $a=-7;b=9$