The pulmonary trunk originates from which of the following?

The first diffraction minimum due to a single slit diffraction is seen at $\theta = 30^o$ for light of wavelength $5000 \, \mathring{A}$ falling perpendicularly on the slit. The width of the slit is

Which of the following statements is incorrect?

In organic reactions,sodium in liquid ammonia is used as

The same retarding force is applied to stop a train. The train stops after $80 \ m$. If the speed is doubled,then the distance will be

The functional kidney of a frog tadpole is