The diagram illustrates how pressure in the left side of the heart and the aorta changes with time. The duration of this cardiac cycle is $0.6\,\text{s}$. Points 1, 2, 3 and 4 show the moments when the atrioventricular valves and semilunar valves open or close. What is the total length of time in one cardiac cycle for which the atrioventricular valves and the semilunar valves are both closed together?
- A$0.03\,\text{s}$
- B$0.04\,\text{s}$
- C$0.07\,\text{s}$
- D$0.21\,\text{s}$