Answer:8 lilies and 12 tulips; total of 20 flowers.
Step-by-step explanation:
8 lilies for $3 each equals $24. 12 tulips for $2 each equals $24. Add that together and the total for the bouquet is $48.
Pandas and combine like terms
Answer:

Step-by-step explanation:
In order to add or subtract numbers in scientific notation, the powers of ten must have the same exponent. In this caes the diameter of an average human body cell is a power of -4 and the diameter of a plant cell is a power of -3. In order to add them, we can move the decimal over for the body cell diameter:

Add the two values: 
Answer:
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