The ratio fo boys to girls is 12:16
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
43 ........................................
Answer:
$25 a lamp
Step-by-step explanation:
First divide $10,000 by 500 lamps to find how much one of them cost
That is $20 a lamp so then multiply .25 *20 or 1/4 *20
you get 5 than add 20 +5=25
Answer:
x = 5
Step-by-step explanation:
The equation of a parabola in vertex form is
y = a(x - h)² + k
(h, k ) are the coordinates of the vertex and a is a multiplier
h(x) = 19(x - 5)² + 6 ← is in vertex form
with vertex (h, k ) = (5, 6 )
The axis of symmetry is a vertical line passing through the vertex
with equation x = 5