Answer:

Explanation:
from snells law we have following relation
is refractive index of air
n' - refractive index of air below
i is angle of incidence = 90 - 1.30 = 88.70^o
r is refraction angle
plugging all value in above formula


Answer:i would say "to treat or prevent injuries"
Explanation: anaerobic exercise is: "high intensity movements preformed in a short period of time."
to treat or prevent injuries you would want to do Aerobic exercise, which is an easy exercise like walking.
Well, Break the problem up into parts.
For speeding up:
The car accelerates at 4 m/s^2 for 3 seconds. Multiplying these values tells you the car reaches a speed of 12 m/s.
Vf^2 = Vi^2 + 2a(Xf - Xi)
12^2 = 0 + 2(4)(Xf - 0)
144 = 8 Xf
Xf = 18 m
For coasting:
The car is at the 12 m/s and does this for 2 seconds.
x = vt = (12)(2) = 24 m
For slowing down:
The car decelerates at 3 m/s^2 to come to a stop at the next sign. From 12 m/s, this would take 12/3 seconds or 4 s.
Vf^2 = Vi^2 + 2a(Xf - Xi)
0 = 12^2 + (2)(-3)(Xf - 0)
-144 = -6 Xf
Xf = 24 m
Summing the distances: Xtotal = 18 + 24 + 24 = 66 m
Answer:
(c) Intrapulmonary pressure
Explanation:
Intrapulmonary pressure is the pressure of air within the alveoli, it changes with the different phases of breathing, and because it is connected to the atmosphere through the throat if eventually equalizes with the atmospheric air pressure in the environment.
Answer:
15.8 ft/s
Explanation:
= Velocity of car A = 9 ft/s
a = Distance car A travels = 21 ft
= Velocity of car B = 13 ft/s
b = Distance car B travels = ft
c = Distance between A and B after 4 seconds = √(a²+b²) = √(21²+28²) = √1225 ft
From Pythagoras theorem
a²+b² = c²
Now, differentiating with respect to time

∴ Rate at which distance between the cars is increasing three hours later is 15.8 ft/s