Question 1: A material that causes a wave to bounce off it is called the. Answer : Reflection
Question 2: A material that takes in a wave when the wave hits is called the. Answer: Absorber
Answer:
True
Explanation:
This is because the statement above fits the definition of a positive economic statement. A Positive economic statement refers to objective statements that can be verified, tested , amended or discarded by consulting available evidence .The statement above can be tested objectively to establish its veracity.
The differences are the freezing and boiling points being exactly 180 degrees
Answer:
Mass, m = 1.51 grams
Explanation:
It is given that,
The circumference of Aluminium cylinder, C = 13 mm = 1.3 cm
Length of the cylinder, h = 4.2 cm
We know that the density of the Aluminium is 2.7 g/cm³
Circumference, C = 2πr

Density is equal to mass per unit volume.

m is mass of the cylinder
V is the volume of the cylinder

So,

So, the mass of the cylinder is 1.51 grams.