The cost of insuring a building is £520 in a particular year.

The following year, the cost of insurance per £10,000 insured increases by 4%.

Also, the insured value of the building increases by 5%.

Calculate the new cost of insuring the building.

1. Insurance that costs £440 per annum if paid in a single payment, costs £38.50 per month if paid in 12 equal monthly installments.

Calculate:

2. the additional annual cost if paying by monthly installments

3. the additional annual cost as a percentage of the single payment cost.