The notation "1.78E12" on Charlee's calculator represents a number in scientific notation, where "E" stands for "exponent". Specifically, "1.78E12" means:
\[ 1.78 \times 10^{12} \]
This means that the number is \( 1.78 \) multiplied by \( 10 \) raised to the power of \( 12 \). In simpler terms, this number is:
\[ 1.78 \times 10^{12} = 1.78 \times 1,000,000,000,000 = 1,780,000,000,000 \]
So, Charlee's calculator is displaying the product of the two large numbers as approximately 1.78 trillion.