<h2>Answer:</h2>
<h2>Explanation:</h2>
First, let's refer to the distance formula:
, where d is distance, v is velocity or speed and t is time.
Now, let's find the distance covered by each individual speed that the car had:
<h3>1. Speed 1.</h3>
In order to use the formula, we need to convert minutes into hours since the speed is given in km/h.
21.1 min/60= 0.35 h.
Now, apply the distance formula.
d=(0.35h)*(86.8km/h)= 30.38 km.
<h3>2. Speed 2.</h3>
Convert minutes to hours again and do the same calculations.
10.6min/60=0.18h
d=(0.18h)*(106km/h)= 19.08 km.
<h3>3. Speed 3.</h3>
36.5min/60= 0.61h
d=(0.61h)*(30.9km/h)= 18.85 km.
<h3>4. Obtain the total distance.</h3>
The total distance must be given by the addition of all individual distances traveled by the car on each speed:
Total distance= 30.38 km + 19.08 km + 18.85 km= 68.31 km.
Answer : The de-Broglie wavelength of this electron, 
Explanation :
The formula used for kinetic energy is,
..........(1)
According to de-Broglie, the expression for wavelength is,

or,
...........(2)
Now put the equation (2) in equation (1), we get:
...........(3)
where,
= wavelength = ?
h = Planck's constant = 
m = mass of electron = 
K.E = kinetic energy = 
Now put all the given values in the above formula (3), we get:


conversion used : 
Therefore, the de-Broglie wavelength of this electron, 
answer:
6 ohms
Explanation:
if these two resistors are connected in series, the total resistance is the sum: 2+4 = 6 (ohms)