q20)When a compound A (C5H12O) is treated with HBr, it forms compound B (C5H11Br). The 1H NMR spectrum of compound A has one singlet integrating to 1 H, two doublets integrating to 3 H and 6 H, and two multiplets each integrating to 1 H. The 1H NMR spectrum of compound B has a singlet integrating to 6 H, a triplet integrating to 3 H, and a quartet integrating to 2 H.Draw the structure of compound B.