The average human body cell is about 5.1 \cdot 10^{-4} \text{ cm}5.1⋅10 −4 cm5, point, 1, dot, 10, start superscript, minus, 4, end superscript, start text, space, c, m, end text in diameter. The diameter of a plant cell is 8 \cdot 10^{-3} \text { cm}8⋅10 −3 cm8, dot, 10, start superscript, minus, 3, end superscript, start text, space, c, m, end text. What is the combined diameter of the body cell and plant cell? Express your answer in scientific notation.