B. For one - month supply 75 ml is needed.
Step-by-step explanation:
First we have to convert mcg (micro gram) to milligram (mg) by using the conversion factor as,
1 mcg = 0.001 mg
So 125 mcg = 125 × 0.001 mg = 0.125 mg
1 ml of Digoxin elixir contains 0.05 mg
Now we need to find the milliliters needed for a day and then for a month.
x =
= 2.5 ml per day
For 30 days we have to multiply 2.5 ml by 30 as,
2.5 ml × 30 = 75 ml is needed for a month.