A human heart pumps about seven times 10 to the power of -2 leaders of blood per heartbeat. The average human heart beats about 72 times per minute. How many liters of blood does a heart pump in one year, and 70 years? Express your answers in scientific notation then use estimation to justify your answers.
a. 1.74 × 10⁷ L
b. 2.31 × 10⁷ L
c. 1.46 × 10⁷ L
d. 2.02 × 10⁷ L
