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
Answer:
breadth: 3 m and area of rectangle: 27 m²
explanation:
part A:
perimeter of rectangle: 2 ( length + breadth )
using the formula:
24 = 2 ( 9 + breadth )
9 + breadth = 12
breadth = 3 m
part B:
area of the rectangle = length * breadth
using the formula:
9 * 3
27 m²
Answer:
3 dogs
Step-by-step explanation:
Idk if the 5 dog was supposed to have a s but if not its 5 btw that's really sad
<h2>Explanation:</h2>
Let's take a look at all of our options.
A. it is also a square
- A rectangle is NOT <em>always </em>a square because a square has congruent sides, so that means all four of its sides are <em>always </em>equal.
- A rectangle <em>can </em>be a square but it can also not be a square, so therefore A cannot be an option because it is not always true about a rectangle.
B. the sum of its angle measures is 360
- This is true because every quadrilateral's angle measures will add up to 360 degrees, no matter what. This is like how a triangle's angle measures always add up to 180 degrees.
- B is an option because it is an ALWAYS true statement.
C. it has four congruent angles
- A rectangle always has 90 degree angles, giving it its shape.
- Since a rectangle always has the same-degree angles, that means that it DOES have four congruent angles.
- C is also an option because it is always true.
D. it has four congruent sides
- A rectangle does not ALWAYS have four congruent sides. Say for example a rectangle has a longer length than its width.
- A square has four congruent sides, but a rectangle is not always a square, therefore this option is not applicable for a rectangle since it is not always true.
<h2>Answers:</h2>
B and C are always true of a rectangle.
Let Sam be (S+8) years while his sister is S years.
S(S+8) = 105
S^2+8S-105 = 0
(S+15)(S-7) = 0
Sam’s sister is 7 years and Sam is 15 years old.