There is a missing part in the question. Found the complete text on internet:
"<span>What is the largest size vehicle (kg) it can lift if the diameter of the output line is 28.0 cm? "
Solution
The diameter of the piston is 28.0 cm, this means its radius is 14.0 cm (half the diameter), so the area of the piston is
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<span>
The maximum pressure of the lift is
</span>

<span>
Therefore the maximum force the piston can lift is
</span>

<span>
And the size (the mass) of the vehicle is
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Ans: Beat Frequency = 1.97HzExplanation:
The fundamental frequency on a vibrating string is

<span> -- (A)</span>
<span>here, T=Tension in the string=56.7N,
L=Length of the string=0.66m,
m= mass = 8.3x10^-4kg/m * 0.66m = 5.48x10^-4kg </span>
Plug in the values in Equation (A)
<span>so </span>

<span> = 197.97Hz </span>
<span>the beat frequency is the difference between these two frequencies, therefore:
Beat frequency = 197.97 - 196.0 = 1.97Hz
-i</span>
Given :
Reem took a wire of length 10 cm. Her friend Nain took a wire of 5 cm of the same material and thickness both of them connected with wires as shown in the circuit given in figure. The current flowing in both the circuits is the same.
To Find :
Will the heat produced in both the cases be equal.
Solution :
Heat released is given by :
H = i²Rt
Here, R is resistance and is given by :

So,
Now, in the question every thing is constant except for the length of the wire and from above equation heat is directly proportional to the length of the wire.
So, heat produced by Reem's wire is more than Nain one.
Hence, this is the required solution.
Answer:
A & D
Explanation:
A single-displacement reaction is a chemical reaction whereby one element is substituted for another one in a compound and thereby generating a new element and also a new compound as products.
From the options, only options A & D fits this definition of single-displacement reactions.
For option D: Both left and hand and right hand sides each have one element and one compound. We can see that K is substituted from KBr to join Cl to form KCl and Br2 on the right hand side.
For option A: Both left and hand and right hand sides each have one element and one compound. We can see that OH is substituted from 2H2O to join Mg to form Mg(OH)2 and H2 on the right hand side.
The other options are not correct because they don't involve only and element and a compound on each side of the reaction.
Answer:
The datapoint 9.0 ppm is outlier at the 90% confidence level.
Explanation:
The old data has following values
mean=10.5 mm
standard deviation 0.2 mm
Now the mean of new values is calculated as following

So the value as 9.0 ppm can be considered easily as outlier in this regard.