1- Analysing seasonality of time series, we obtained the output shown below.

ice.cream.sale refers to ice-cream sales in hundreds of kilograms, qj is a dummy indicator of quarter j.

i- Formulate the null hypothesis of a suitable test to find out whether seasonal pattern exhibits statistically significant.

ii- What is the interpretation of the estimated intercept? Does it make any sense?

iii- What is the interpretation of the estimated coefficient of the dummy variable q3?