Dennis is paid $15 an hour for the first 40 hours per week that he works.

He can also work as many hours overtime as he wishes.

He is paid $30 an hour for every hour that he works beyond 40 hours a week.

Leisure is a normal good for Dennis and he is currently working some overtime.

If his hourly wage for the first 40 hours per week that he works rises to $20 and his wages for overtime remain at $30 per hour, he will choose to work:

The same number of hours per week

More hours per week

Fewer hours per week

More hours per week only if the income effect of the wage increase outweighs the substitution effect of the wage increase

Fewer hours per week only if he has no non-labour income.

Which statement is correct? Please show steps.