Answer:
Speed of air = 1106.38 ft/s
Explanation:
Speed of sound in air with temperature

Here speed is in m/s and T is in celcius scale.
T = 50°F

Substituting

Now we need to convert m/s in to ft/s.
1 m = 3.28 ft
Substituting

Speed of air = 1106.38 ft/s
Average speed =
(total distance)/(total time)
Average speed = (99+90)/(2+3)
That's (189 km) / (5 hr)
Average speed = 37.8 km/hr
Answer:
B meet A 0.01 km east of flagpole
Explanation:
given data
distance A = 5.7 km west
velocity V1 = 8.9 km/h
distance B = 4.5 km east
velocity V2 = 7 km/h
to find out
How far runners from the flagpole, when paths cross
solution
we know A and B are 5.7 + 4.5 = 10.2 km apart
and we consider here B will run distance x km for meet
so time will be for B is
time B = distance / velocity
time B = x / 7 ...................1
and
for A distance for meet = ( 10.2 - x ) km
so time A = distance / velocity
time A = ( 10.2 - x ) / 8.9 .............2
now equating equation 1 and 2
time A = time B
x / 7 = ( 10.2 - x ) / 8.9
x = 4.490
so distance of B run for meet is 4.490 km
so distance from the flagpole when their paths cross is 4.5 - 4.490 = 0.01 km
so B meet A 0.01 km east of flagpole
Choice-'b' says the formula for kinetic energy in words.
KE = (1/2) · (M) · (S²)
So we want to know what will happen if we put a magnetically soft material in a strong magnetic field. A magnetically soft material is a material whose magnetic field can easily be reversed. Those are ferromagnetic materials. Iron is such a material. When a magnetically soft material is placed into a strong magnetic field it gets its own magnetic field. But its not a permanent magnetic field, it can be changed by a different strong magnetic field.