Analytical techniques: explain question

The 1H NMR spectrum of propan-1-ol ($\ce{CH3CH2CH2OH}$) is obtained using $\ce{CDCl3}$ as solvent and TMS as reference. The spectrum displays four signals: a triplet at $\delta$ 0.9 (integration 3H), a multiplet at $\delta$ 1.5 (integration 2H), a triplet at $\delta$ 3.6 (integration 2H), and a broad singlet at $\delta$ 2.1 (integration 1H) which disappears when the sample is shaken with $\ce{D2O}$. Explain how each feature of the spectrum (chemical shift, integration, splitting pattern, and the $\ce{D2O}$ exchange) allows you to assign each signal to a specific proton environment.