= Solution
The nested-model $F$-test has hypotheses
$$
H_0:\beta_1=\beta_2=0,
\qquad
H_1:(\beta_1,\beta_2)\ne(0,0).
$$
Its statistic is
$$
F=\frac{(1704.9-1477.7)/2}{1477.7/170}=13.069.
$$
The reported $p$-value $5.252\times10^{-6}$ gives strong evidence against $H_0$: weight and width are jointly useful.
Neither individual coefficient is significant at $5\%$. This is consistent with the predictor correlation $0.877$: strong <multicollinearity> makes the two partial effects difficult to distinguish and inflates their individual standard errors, even though their joint contribution is clear.
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