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
cos A is 0.8511 and tan B is 1.6
Step-by-step explanation:
Find the 3rd length or the hypotenuse.
<u>Pythagoras theorem</u>
=
+ 
=
+ 
= 64 + 25
hypotenuse = 
hypotenuse = 9.4
a) Cos A
<u>Data:</u>
Adjacent = 8
Hypotenuse = 9.4
<u>Formula:</u>
Cos (Angle) = 
Cos A = 
Cos A = 0.8511
A =
(0.8511)
A = 31.7°
b) Tan B
<u>Data: </u>
Opposite = 8
Adjacent = 5
<u>Formula:</u>
Tan (Angle) = 
Tan B = 
Tan B = 1.6
B =
(1.6)
B = 58°
Therefore, cos A is 0.8511 and tan B is 1.6.
Keyword: cos, tan
Learn more about cos at
#LearnwithBrainly
Answer:
13,000
Step-by-step explanation: 10% of 31,000= 3,100 x 6= 18,600
31,000-18,600=13,000
Yes that is right all the numbers are in the right place value in the decimals are in the right place value
Answer:
135 !!!!!!!!!!!!
Step-by-step explanation:
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