The monomer of $[-C(CH_3)_2 - CH_2-]_n$ is ...

Which one of the following halogens liberates oxygen,when passed through hot concentrated $KOH$ solution?

What is the decreasing order of reactivity of $HX$ in the given reaction: $ROH + HX \rightarrow RX + H_2O$?

$A$ river of salty water is flowing with a velocity $2 ~m/s$. If the density of the water is $1.2 ~g/cc$,then the kinetic energy of each cubic metre of water is

$A$ particle at the end of a spring executes simple harmonic motion with a period $t_1$,while the corresponding period for another spring is $t_2$. If the period of oscillation with the two springs in series is $T$,then

Which of the following factors increase the heart rate?
$(a)$ Sympathetic nerve signals
$(b)$ Parasympathetic nerve signals
$(c)$ Adrenal medullary hormones
$(d)$ Vagus nerve
$(e)$ Thyroxine hormone
$(f)$ Acetylcholine