Water that flows across the surface is called a;
Runoff
That's when rain has saturated the ground to the point it cant hold anymore and it runs over the surface.
 
        
             
        
        
        
Answer:
The mass of the mud is 3040000 kg.
Explanation:
Given that,
length = 2.5 km
Width = 0.80 km
Height = 2.0 m
Length of valley = 0.40 km
Width of valley = 0.40 km
Density = 1900 Kg/m³
Area = 4.0 m²
We need to calculate the mass of the mud
Using formula of density


Where, V = volume of mud
 = density of mud
 = density of mud
Put the value into the formula


Hence, The mass of the mud is 3040000 kg.
 
        
             
        
        
        
Answer:
c. expanded polyurethane
Explanation:
Thermal performance of a building fabric is measured in terms of heat loss and is expressed as U-value or R-value. U-value is the rate of heat transferred through a structure divided by the difference in temperature across the structure with a unit of measurement of W/m²K.You can calculate the U-value of a by getting the reciprocal of the sum of thermal resistances , R, making the building material.
If you have the value of R, then U=1/R
Material                         size            R                      U
plywood                          1"              1.25                0.8
Poured concrete            2"              0.99               1.010
Expanded polyurethane  1"            6.5                   0.1538
Asbestos shingles            1"             0.03                33.33
The material with lowest U-value is expanded polyurethane
 
        
             
        
        
        
Explanation:
Let  is the mass of proton. It is moving in a circular path perpendicular to a magnetic field of magnitude B.
 is the mass of proton. It is moving in a circular path perpendicular to a magnetic field of magnitude B. 
The magnetic force is balanced by the centripetal force acting on the proton as :

r is the radius of path,

Time period is given by :


Frequency of proton is given by :

The wavelength of radiation is given by :


So, the wavelength of radiation produced by a proton is  . Hence, this is the required solution.
. Hence, this is the required solution.