Which among the following is an example of a zero order reaction?

The rates of a certain reaction $(dc/dt)$ at different times are as follows:

Time $(sec)$	Rate $(mole \ litre^{-1} \ sec^{-1})$
$0$	$2.8 \times 10^{-2}$
$10$	$2.78 \times 10^{-2}$
$20$	$2.81 \times 10^{-2}$
$30$	$2.79 \times 10^{-2}$

The reaction is:

For the reaction $A \longrightarrow 3 B$,the rate is given by $rate = k[A]^0$. Based on the data provided in the table,what is the concentration of the product $B$ (in $mol \ L^{-1}$) after $20 \ s$?

Time $(s)$	Concentration of the reactant $(mol \ L^{-1})$
$0$	$0.1$
$15$	$0.05$
$20$	$0.1 - x$

For a certain reaction,$10\%$ of the reactant dissociates in $1 \ hour$,$20\%$ of the reactant dissociates in $2 \ hour$,and $30\%$ of the reactant dissociates in $3 \ hour$. What are the units of the rate constant?

For a general reaction $A \to B$,a plot of the concentration of $A$ versus time is given in the figure. Answer the following questions based on this graph:
$(i)$ What is the order of the reaction?
$(ii)$ What is the slope of the curve?
$(iii)$ What are the units of the rate constant?

The formation of gas at the surface of tungsten due to adsorption is a reaction of which order?