<h2>a) Average velocity in first 4 seconds is 64 ft/s upward</h2><h2>b) Average velocity in second 4 seconds is 63.5 ft/s downward</h2>
Explanation:
a) Given S(t) = 76 + 128t − 16t²
s(0) = 76 + 128 x 0 − 16 x 0² = 76 ft
s(4) = 76 + 128 x 4 − 16 x 4² = 332 ft
Displacement in 4 seconds = 332 - 76 = 256 ft
Time = 4 - 0 = 4 s

Average velocity in first 4 seconds is 64 ft/s upward
a) Given S(t) = 76 + 128t − 16t²
s(4) = 76 + 128 x 4 − 16 x 4² = 332 ft
s(8) = 76 + 128 x 8 − 16 x 8² = 78 ft
Displacement in 4 seconds = 78 - 332 = -254 ft
Time = 4 - 0 = 4 s

Average velocity in second 4 seconds is 63.5 ft/s downward
As a liquid is cooled its molecules lose kinetic energy and their motion slows. When they've slowed to where intermolecular attractive forces exceed the collisional forces from random motion, then a phase transition from liquid to solid state takes place and the material freezes
Hope it helps u
FOLLOW MY ACCOUNT PLS PLS
Answer:
An aircraft flying at sea level with a speed of 220 m/s, has a highest pressure of 29136.8 N/m²
Explanation:
Applying Bernoulli's equation, we determine the highest pressure on the aircraft.

where;
P is the highest pressure on the aircraft
is the density of air = 1.204 kg/m³ at sea level temperature.
V is the velocity of the aircraft = 220 m/s
P = 0.5*1.204*(220)² = 29136.8 N/m²
Therefore, an aircraft flying at sea level with a speed of 220 m/s, has a highest pressure of 29136.8 N/m²