Answer:
a) 0.658 seconds
b) 0.96 inches
Explanation:

Time taken by the ball to reach the highest point is 0.14 seconds

The highest point reached by the snowball above its release point is 0.315 ft
Total height the snowball will fall is 4+0.315 = 4.315 ft

The snowball will reach the bank at 0.14+0.518 = 0.658 seconds after it has been thrown


The snowball goes 0.5-0.42 = 0.08 ft = 0.96 inches
Answer: The intensity level of sound in the bedroom is 80dB
Explanation:
Intensity of lawn mower at r=1m is 100dB
Beta1= 10dBlog(I1/Io)
100dB= 10dB log(I1/Io)
10^10= I1/Io
I1= Io(10^10)
10^12)×(10^10)= I1
I1=10^-2w/m^2
Intensity of lawn mower at r=20m
I2/I1=(r1/r2)^2 =(1/20)^2
I2= I1(1/400)
I2=2.5×10^-3W_m^2
Intensity of 4 lown mowers at 20m fro. Window
= 10dBlog(4I2/Io)
= 10^-4/10^-12
=80dB
The ease with which a material allows electricity to move is called
C. CONDUCTIVITY