Identify the diene and dienophile that will yield the given product in a Diels‑Alder reaction, and identify the second major product of the reaction, by dragging the appropriate structures to the boxes.

City a and city b had two different temperatures on a particular day. on that day, four times the temperature of city a was 8â° c more than 3 times the temperature of city b. the temperature of city a minus twice the temperature of city b was â’3â° c. what was the temperature of city a and city b on that day? city a was 5â° c, and city b was 4â° c. city a was 3â° c, and city b was â’1â° c. city a was 8â° c, and city b was â’3â° c. city a was 5â° c, and city b was â’5â° c.

)benzene and toluene form nearly ideal solutions. consider an equimolar solution of benzene and toluene. at 20 °c the vapour pressures of pure benzene and toluene are 9.9 kpa and 2.9 kpa, respectively. the solution is boiled by reducing the external pressure below the vapour pressure. calculate (i) the pressure when boiling begins, (ii) the composition of each component in the vapour, and (iii) the vapour pressure when only a few drops of liquid remain. assume that the rate of vaporization is low enough for the temperature to remain constant at 20 °c.

Structure of the atoms: discovery of the nucleus in 1909i need answering all of these questions