Answer:
Human activities and natural processes have influenced the change in the global temperature by the following processes
1) Green house gas such as carbon dioxide, methane, ozone, nitrous oxide and fluorinated gases produced by the combustion of fossil fuels the use of  industrial chemicals, the production of coal, and natural gas
2) Deforestation which reduces the natural process of conversion of carbon dioxide to oxygen, thereby, increasing the greenhouse gases in the atmosphere
3) The accumulation of the greenhouse gases in the atmosphere results in the trapping of heat in the atmosphere, causing the atmospheric temperature to rise
4) Changes in the amount of energy produced by the Sun can result in an increase or decrease in the atmospheric temperature
5) Volcanic activity that occurs at a sufficiently large scale can produce sulfur dioxide that blocks the rays of the Sun from reaching the Earth, resulting in a change of atmospheric temperature.
Explanation:
 
        
             
        
        
        
You need to use Planck's law:
E = h·υ = (h·c)/λ
Without making all the calculations, a fraction is bigger than another when the denominator is smaller. Therefore you need to find the smallest wavelength (λ) which is 450nm.
You could also be helped by colors: in order of decreasing energy, you have blue - green - yellow - red.
In any case, the correct answer is a).
        
             
        
        
        
Answer:
32.76 Volt
Explanation:
frequency, f = 400 Hz
Area of crossection, A = 13 cm²
Maximum flux density, B = 0.9 tesla 
Number of turns in secondary coil, N = 70 
Let the maximum induced voltage is e.
According to the Faraday's law of electromagnetic induction, the induced emf is equal to the rate of change of magnetic flux. 
e = dФ/dt 

Time is defined as the reciprocal of frequency. 
So, e = N B A f 
e = 70 x 0.9 x 13 x 10^-4 x 400 
e = 32.76 volt
 
        
             
        
        
        
1.Use the balance to find the mass of the object. Record the value on the "Density Data Chart."
2.Pour water into a graduated cylinder up to an easily-read value, such as 50 milliliters and record the number.
3.Drop the object into the cylinder and record the new value in millimeters.
4.The difference between the two numbers is the object's volume. Remember that 1 milliliter is equal to 1 cubic centimeter. Record the volume on the data chart.
5.Compute the density of the object by dividing the mass value by the volume value. Record the density on the data chart.