You haven't told us what the passing percentage is on the exam,
or what the passing percentage is for the semester, or any of that.
So we want to know what changes inside the multimeter when we change the voltage range from 200 V to 20 V, by what factor and does it increase or decrease. What we want when trying to measure the voltage with a multimeter is that a minimal current passes trough the mulitmeter so when we change the voltage range, we decrease the resistance by a factor of 10 because the voltage is decreased by a factor of 10.
Explanation:
It is given that,
Mass of concrete pilling, m = 50 kg
Diameter of wire, d = 1 mm
Radius of wire, r = 0.0005 m
Length of wire, L = 11.2
Young modulus of steel, 
The young modulus of a wire is given by :





So, the wire will stretch 0.034 meters. Hence, this is the required solution.
Answer:
7.19 * 10^14J
Explanation:
Given that
Density of water Pwater= 1000kg/m3
R=2.1km = 2.1*10^3m
H= 2.3cm. = 2.3*10^-2m
Lv water= 2256 * 10^3J/kg
First, mass of water need to be calculated, using an imaginary cylinder
Density= Mass /Volume
Mass= Density* Volume
Volume of a cylinder= πR2h
Therefore mass= PπR2H
= 1000 * π * (2.1 *10^3)^2 * (2.3 * 10^-2)
= 3.18 *10^8
Heat Released Qv = mLV
= 3.18*10^8 * 2236*10^3
= 7.19 * 10^14J