Name two different numbers that round to 8.21 when rounded to the nearest hundredth

What is the sum of these mixed numbers 2 1/8 + 4 3/8

The average human heart beats 1.15 \cdot 10^51.15⋅10 5 1, point, 15, dot, 10, start superscript, 5, end superscript times per day. there are 3.65 \cdot 10^23.65⋅10 2 3, point, 65, dot, 10, start superscript, 2, end superscript days in one year.how many times does the heart beat in one year? write your answer in scientific notation, and round to one decimal place.

If f(x) =3x-2 and g(x) =2x+1 fins (f+ g) (x)