You need to expand the brackets eg.
(w-9)8 basically means 8 x (w-9) = 8w-72
Answer:
Carbon dioxide is added to the atmosphere naturally when organisms respire or decompose (decay), carbonate rocks are weathered, forest fires occur, and volcanoes erupt. Carbon dioxide is also added to the atmosphere through human activities, such as the burning of fossil fuels and forests and the production of cement.
Step-by-step explanation:
Just replace a with 4 and b with 2 and your equation looks like
3.14 (4×2+4×2)
solve within the parenthesis first
3.14 (8+8)
3.14 (16) =50.24