A survey of 115 men and 125 women produced the result that the mean amount of tea consumed by the men in a month's time was 0.67 litres, compared with a a mean of 0.54 litres for the women. The variance of tea consumption for men was 25% higher than that for women.

A 95% confidence interval for the difference between the means (men's mean - women's mean) was found to be [-0.07, L] .

Find L (two decimal places).

That is all the information I have in the question. Please help me. Thank you