The equation used to predict the weight of an elephant (in kilograms) is

ŷ = -4016 + 11.5x₁ + 7.55x₂ + 12.5x₃

where x₁ represents the girth of the elephant (in centimeters), x₂ represents the length of the elephant (in centimeters), and x₃ represents the circumference of a footpad (in centimeters).

(a) x₁ = 421, x₂ = 224, x₃ = 144

(b) x₁ = 311, x₂ = 171, x₃ = 102

(c) x₁ = 376, x₂ = 226, x₃ = 124

(d) x₁ = 231, x₂ = 135, x₃ = 86

Use the multiple regression equation to predict the y-values for the values of the independent variables.