A dog has three puppies. Spot weighs 12 ounces. Rascal weighs 9.5 ounces. Socks weighs 10.2 ounces. What is the total weight of the litter expressed to the correct number of significant figures?
A) 31.7 ounces
B) 31 ounces
C) 32 ounces
D) 30 ounces
E) 31.70 ounces
Question 2
Two fixed navigation beacons mark the approach lane to a star. The beacons are in line with the star and are 65 Mm apart. A spaceship approaches the star with a relative velocity of 0.90 c and passes the beacons.
As the ship passes the first beacon the ship emits a short radar pulse toward the second beacon, and the radar echo is received at the ship. The time interval between the emission of the radar pulse and the reception of the radar echo is closest to: A) 230 ms
B) 520 ms
C) 150 ms
D) 99 ms
E) 60 ms