Requesting a tutors help in explaining this question. I found different answers on course hero, so I'm confused and need help explaining.

Let's assume that cigarettes have a price elasticity of demand = -0.4. If the government wants to decrease the quantity consumed of cigarettes 30%, what percentage of tax would they have to levy on cigarette consumption?

a.1.3%

b.12%

c. 75%

d. 85%