Answer:
umm what
Step-by-step explanation:
Answer:
correct option is C) 2.8
Step-by-step explanation:
given data
string vibrates form = 8 loops
in water loop formed = 10 loops
solution
we consider mass of stone = m
string length = l
frequency of tuning = f
volume = v
density of stone =
case (1)
when 8 loop form with 2 adjacent node is
so here
..............1

and we know velocity is express as
velocity = frequency × wavelength .....................2
= f ×
here tension = mg
so
= f ×
..........................3
and
case (2)
when 8 loop form with 2 adjacent node is
..............4

when block is immersed
equilibrium eq will be
Tenion + force of buoyancy = mg
T + v ×
× g = mg
and
T = v ×
- v ×
× g
from equation 2
f ×
= f ×
.......................5
now we divide eq 5 by the eq 3

solve irt we get

so
relative density 
relative density = 2.78 ≈ 2.8
so correct option is C) 2.8
Isolate the variable by dividing each side by factors that don't contain the variable.
f=e-g/d
The correct answer is:
[B]: "

" .
__________________________________________________________Consider choice [A]: 
;
=

;
= 2 ; "2 ≠ -2" ; so we can rule out: "Choice [A]" .
__________________________________________________________Consider choice [B]: 
;
=

;
= "-2" ; Yes!
→ Let us proceed with the final answer choice ;
__________________________________________________________Consider choice [C]:

;
=

;
= 2 ; "2 ≠ -2" ; so we can rule out: "Choice [C]" .
__________________________________________________________The correct answer is:
[B]: "

" .
__________________________________________________________
.......................................