Answer:
a) 
b) 
c) 
d) Displacement = 22 m
e) Average speed = 11 m/s
Explanation:
a)
Notice that the acceleration is the derivative of the velocity function, which in this case, being a straight line is constant everywhere, and which can be calculated as:

Therefore, acceleration is 
b) the functional expression for this line of slope 4 that passes through a y-intercept at (0, 3) is given by:

c) Since we know the general formula for the velocity, now we can estimate it at any value for 't", for example for the requested t = 1 second:

d) The displacement between times t = 1 sec, and t = 3 seconds is given by the area under the velocity curve between these two time values. Since we have a simple trapezoid, we can calculate it directly using geometry and evaluating V(3) (we already know V(1)):
Displacement = 
e) Recall that the average of a function between two values is the integral (area under the curve) divided by the length of the interval:
Average velocity = 
Time = (distance) / (speed)
Time = (0.25 km) / (65 km/hr)
<em>Time = 0.00385 hour</em>
(That's 13.85 seconds.)
<u />
<u>Better way:</u>
Distance = 0.25 km
Distance = 250 meters
Speed = (65 km/hr) x (1000 m/km) x (1 hr/3600 sec)
Speed = 18.06 m/sec
Time = (250 m) / (18.06 m/s)
<em>Time = 13.85 seconds </em>
Answer: Cell's nucleus
Explanation :
The full form of DNA is Deoxyribonucleic acid. The genetic information of a cell is organized in the DNA. It is inherited from parents by their children.
DNA is coiled into chromosomes in a cell's nucleus. It has a shape like a double helix. It is twisted in the form of spirals.
Hence, DNA is coiled into chromosomes in a cell's Nucleus.
<span>Refraction is where the direction of travel of sound waves is altered by passing through a material of much higher or lower density. Walls that allow sound through are one example, but answer B is more about walls bouncing sound back - that's an example of reflection. The most likely change of density is answer A, air with big temperature differences.</span>
These energy exchanges are not changes in kinetic energy. They are changes in bonding energy between the molecules. If heat is coming into a substance during a phase change, then this energy is used to break the bonds between the molecules of the substance. The example we will use here is ice melting into water.