= Solution
The <Wald test> of $H_0:\beta=0$ uses
$$
Z=\frac{6.73}{8.04}=0.837,
$$
with an approximate <standard normal distribution> under the null. Its two-sided <p-value> is $0.403$, and the approximate $95\%$ <Wald confidence interval> is
$$
\boxed{6.73\pm1.96(8.04)=(-9.03,22.49).}
$$
\b[There is no convincing evidence of a covariate effect, and the slope is very imprecisely estimated.] The model can fit acceptably while its slope is statistically indistinguishable from zero. In the <Poisson regression>, a unit covariate increase multiplies the mean by $e^\beta$; exponentiating the two interval limits shows how poorly this multiplier is determined on the stated scale. One might compare with an intercept-only model using a <likelihood-ratio test>, but its numerical deviance difference is not supplied. Failure to reject does not establish no effect.
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