8. Calculate the semi-annual rate convertible monthly, from 38% convertible semi-annually. 9. To pay for a certain item with a value of $5,000, 3 payments were agreed: a 30% down payment, a second payment per month, and a third payment of $1,700 at 3 months. What is the value of the second payment with 42% interest? 12. What instantaneous rate is equivalent to a rate of 28% convertible monthly?