False I think
Hope this helped ^^;
Answer:
64°
Explanation:
The triangle is an isosceles triangles (both legs are equal to the radius of the circle), so that means the base angles are the same.
Angles of a triangle add up to 180°, so:
128 + 2x = 180
2x = 52
x = 26
∠1 is complementary to the base angle, so:
∠1 = 90 − 26
∠1 = 64
Distance/ time = 100/5 = 20 km per hour
The average speed at 5hrs is 20 km per hour.
Properties to identify a mineral:
Color
Luster
Streak
Hardness
Cleavage
(There appears to be 8 things you need to fill in but I only know this much)
What will scratch Quartz:
Topaz
Corundum
Diamond
sorry I only knew a few of the answers, hope I still helped
(a) 
The frequency of an electromagnetic wave is given by:

where
is the speed of the wave in a vacuum (speed of light)
is the wavelength
In this problem, we have laser light with wavelength
. Substituting into the formula, we find its frequency:

(b) 427.6 nm
The wavelength of an electromagnetic wave in a medium is given by:

where
is the original wavelength in a vacuum (approximately equal to that in air)
is the index of refraction of the medium
In this problem, we have

n = 1.48 (index of refraction of glass)
Substituting into the formula,

(c) 
The speed of an electromagnetic wave in a medium is

where c is the speed of light in a vacuum and n is the refractive index of the medium.
Since in this problem n=1.48, we find
