Final answer:
The number 3*10^9 is commonly displayed as '3E9' on a scientific calculator, using the E notation for exponent in scientific notation.
Step-by-step explanation:
A common way for a scientific calculator to show the number 3*109 is option C. 9E3. Scientific calculators often use the E or e notation to represent powers of 10, which is a compressed format of writing numbers in scientific notation. The letter E (or e) stands for exponent and is followed by the power of 10. So, the number 3*109 would be displayed as 3E9 on many calculators.
Scientific notation simplifies the arithmetic of large numbers by separating a number into a coefficient and a power of 10. This compact form is extremely useful when working with very large or very small numbers, making it easier to perform calculations like multiplication or division without handling many zeros. For instance, multiplying (4.506 × 104) × (1.003 × 102) in scientific notation would involve multiplying the coefficients (4.506 and 1.003) and adding the exponents (4 and 2).