Answer:
0.5
Step-by-step explanation:
you can first prepare 0.5 solution (0.5g per 100ml) and for 0.25 0.1,0.025 and 0.05% respectively,dilute to half one fifth one twentieth and one tenth for example add 9 ml water to 1 ml of the stock solution to 10times dilute and obtain a concentration of 0.055
