1. Investigate the joint impact of salary and the number of children on the amount spent. To that end, run a regression model with "AmountSpent" as the response and "Salary" and "Children" as the only 2 predictors. Then, answer the following questions:

Tips:

lm(formula = AmountSpent ~ Salary + Children, data = d)

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1.822e+024.534e+01 4.019 6.3e-05 ***

Salary 2.236e-02 6.635e-0433.704 < 2e-16 ***

Children -2.356e+021.933e+01 -12.191 < 2e-16 ***

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Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.'0.1 ' ' 1

Residual standard error: 641.3 on 997 degrees of freedom

Multiple R-squared: 0.5557,Adjusted R-squared: 0.5548

F-statistic: 623.4 on 2 and 997 DF, p-value: < 2.2e-16

Question: Do salary and number of children have both the same relationship with amount spent?