Your answers for a), b), and c) are correct. Good work !
d). The high noise levels in Technology and PE are more of
a concern to the teachers than to the students because the
students are only in there for 1 or 2 periods a day, but the
Technology and PE teachers are in there ALL day.
e). Mr. Jones can't hear as high frequency as Jenny can because
he is much older than Jenny is. Sadly, even without damage due to
loud noise, the ability to hear high frequencies does decrease with age.
f). The wooden surfaces in the gym cause the gym to be louder
than it would be if it had carpet on the floor. Carpet ... and soft
walls and ceilings ... absorb a lot of the sound that hits them.
But hard surfaces don't absorb much of the sound that hits them,
so it just keeps bouncing around until it finally fades away.
You can see this easily ... just go into the gym at your school, clap
your hands once, and notice how long you keep hearing the sound
after you clap.
Answer:
Regulus
Explanation:
Which is 77.63 light years away
Answer:
Option B

Explanation:
Given information
Radius of container, r=12cm=12/100=0.12m
Angular velocity= 2 rev/s, converted to rad/s we multiply by 2π
Angular velocity, 
We know that speed, 
Centripetal acceleration,
and substituting
we obtain that

Substituting \omega for 12.56637061 and r for 0.12

Rounded off, 
1km=10^3 m,1km^3=10^9cubic metres answer is 1.4x10^18cubic meters