Felix want to work out how much it costs him to use his tumble dryer. The tumble dryer uses 1.9 units of electricity to dry one load of washing.
Felix dries four loads of washing each week.
He pays 12.8p for every unit of electricity he uses.
Work out the weekly cost, in pence, of using the tumble dryer.

A3cm×3cm\greend{3\,\text{cm} \times 3\,\text{cm}} 3cm×3cm start color greend, 3, space, c, m, times, 3, space, c, m, end color greend rectangle sits inside a circle with radius of 4cm\blued{4\,\text{cm}} 4cm start color blued, 4, space, c, m, end color blued . what is the area of the shaded region? round your final answer to the nearest hundredth.