A certain radioactive isotope placed near a Geiger counter registers 120 counts per minute. If the half-life of the isotope is one day, what will be the count rate at the end of four days?
A) 30 counts/min
B) 15 counts/min
C) 10 counts/min
D) 7.5 counts/min
E) 5 counts/min
Answer: D
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Projectile Motion: At a location where g = 9.80 m/s2, a projectile returns to its original height after 4.08 seconds, during which time it travels 76.2 meters horizontally. If air resistance can be neglected, what was the projectile's initial speed?
Fill in the blank(s) with the appropriate word(s).
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