Vacuum strength is rated in terms of
a. torque.
b. horsepower.
c. cm or in. of water lift.
d. rheostat capacity
update: i just completed the pennfoster exam and it was c. cm or in. of water lift.

The star betelgeuse is about 600 light-years away. if it explodes tonight, a. we'll know because debris from the explosion will rain down on us from space.b. we'll know it immediately because it will be brighter than the full moon in the sky.c. we won't know about it until 600 years from now.d. none of the above.