$7\mathrm{.}12$ Drill rig operations. In January $2021,$ an energy finance analysis study by the Institute for Energy Economics and Finance Analysis reported that the price volatility of liquefied natural gas $($LNG$)$ will increase in $2021$ due to delays in drilling activity for shale oil and gas in $2020.$ It was reported that, internationally, drill rig operations were down by $40\%$ over the year $2020.$

a$.$ Identify the parameter of interest.

b$.$ Give the null and alternative hypotheses for testing the reported decreased percentage of drill rig operations.

c$.$ Describe a Type I error in the words of the problem.

d$.$ Describe a Type II error in the words of the problem.