The statement “Electrons are pulled closer to the oxygen
atom” correctly describes the electrons in a water molecule. The
correct answer between all the choices given is the second choice or letter B. I
am hoping that this answer has satisfied your query and it will be able to help
you in your endeavor, and if you would like, feel free to ask another question.
Question
What is the length of the pipe?
Answer:
(a) 0.52m
(b) f2=640 Hz and f3=960 Hz
(c) 352.9 Hz
Explanation:
For an open pipe, the velocity is given by

Making L the subject then

Where f is the frequency, L is the length, n is harmonic number, v is velocity
Substituting 1 for n, 320 Hz for f and 331 m/s for v then

(b)
The next two harmonics is given by
f2=2fi
f3=3fi
f2=3*320=640 Hz
f3=3*320=960 Hz
Alternatively,
and 

(c)
When v=367 m/s then

C2H5OH (l) + 3 O2 (g) = 2 CO2 (g)+ 3 H2O (l/g)
Answer:
4 m/s²
Explanation:
When the elevator is 1 m below point of contact , compression will be 1 m.
Restoring force in the spring will be 10600 N. Friction force of 17000N will also act in upward direction . The weight of 2000 x 9.8 N will act downwards
Force in down ward direction = 2000 x 9.8
= 19600 N
Force in upward direction
= 10600 + 17000
= 27600 N
Net force in upward direction
= 27600 - 19600
= 8000 N
Acceleration in upward direction
= 8000 / 2000
= 4 m/s²