(c) Stack the measurements made on these three occasions into a single variate and perform a newanalysis by mixed modelling. Include the following variables in your initial model:

(i) The time at which the measurement was made.

(ii) The fibre diameter from the same sheep during the pre-experimental period.

(iii) The live weight of the sheep during the pre-experimental period.

Determine whether any terms can reasonably be dropped from the model. If so, make the appropriate changes and re-fit the model.