Linearity of the Model Problem 6. Which of the following 5 models can be stated as a multiple linear regression model, possibly after some variable transformations or other mathematical operations, such that parameters ll, 52, and g can be estimated by OLS? a) ya: = 131 Wig: $53 -exp(,') 13) ya: = 1 + 92;?\" $27533 + 51': C) 5i + 51 = 1323?? + a- 3h: d) ya: =151 +2$1i+ m-l' 512 yr + [31 e) = 6,; 522711: + 13313227 Note: If some adjustments are required, briey state the required operations and the resulting multiple linear regression equation that can be estimated by OLS. If the param- eters cannot be estimated by OLS, briey point out the