coefficients: $(1$ not defined because of singularities Estimate Std$.$ Error t value Pr$(>|$t$|)($Intercept$)685.605417.4727491\mathrm{.}748<2$e$-16***-1.146080.38136-3\mathrm{.}0050.00282-0.648510.03939-16.464<2$e$-16***0.438201.984020.2210.825311.396212.006930.6960.487013.387042.025051.6730.09517$ NA NA NA NA Suppose you run a regression model called modell with three regressors and you get the following output in R after running summary$($modell$).$ Please show the potential issue$($s$)$ with this model and show how you could fix$$the$$problems$.$