Quick questions on The least-squares regression line for HSC Maths Standard 2

The gradient $m$ has units of (y units) per (x unit). For every $1$-unit increase in $x$, the model says $y$ changes by $m$ units on average.

The intercept $b$ is the predicted $y$ value when $x = 0$. In context this is sometimes meaningful (a base salary at zero years of experience, say) and sometimes pure extrapolation (predicted food spending at zero income, which no real household has).

The gradient has units of (y units) per (x unit). Include them explicitly.