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As we know that  Let the distance x and time taken be t.  Now According to the question, And From (1) we have Putting this on (2), we get Since speed can never be negative, we choose, Hence the speed of the train is 40 km/hour.  
Let the points (1, 5), (2, 3), and (- 2,-11) be representing the vertices A, B, and C of the given triangle respectively. Let A = (1, 5), B = (2, 3) and C = (- 2,-11) So The distance AB : The distance BC : The distance CA : As we can see that   AB + BC ≠ CA Therefore, the points (1, 5), (2, 3), and ( - 2, - 11) are not collinear.
  by euclid division lemma,we know that If a and b are two positive integers, then,by euclid division lemma  a = bq + r, 0  r  b Let b = 3 Therefore, r = 0, 1, 2 Therefore, a = 3q or a = 3q + 1 or a = 3q + 2 If a = 3q:  If a = 3q + 1 : If a = 3q + 2 : Therefore, the square of any positive integer is either of the form 3m or 3m + 1. 
Let a be any positive integer a=6q+r where 0 < or = r < 6 put r=1: a=6q+1 which is an odd integer r=3: a=6q+3 which is an odd integer r=5: a=6q+5 which is an odd integer therefore, any positive odd integer is of form 6q+1,6q+3 or 6q+5, where q is some integer.  
Two of the zeroes of the given polynomial are . Therefore two of the factors of the given polynomial are  and     is a factor of the given polynomial. To find the other factors we divide the given polynomial with    The quotient we have obtained after performing the division is  (x+1)2 = 0 x = -1 The other two zeroes of the given polynomial are -1.
Advantages of sexual reproduction: 1. In sexual reproduction, more variations are produced. Thus, it ensures the survival of species in a population. 2. The newly formed individual has characteristics of both the parents. 3. Variations are more viable in sexual mode than in asexual one. This is because, in asexual reproduction, DNA has to function inside the inherited cellular apparatus.
Let the number of days taken by woman and man be x and y respectively, The proportion of Work done by a woman in a single day The proportion of Work done by a man in a single day  Now, According to the question, Also,   Let,  Now, our equation becomes And By Cross Multiplication method, So,
Nuclear energy has the following advantages: (i) It's calorific value is much larger than conventional fossil fuels. (ii) By regulating rate of nuclear fission energy can be generated at very high rate. (iii) Nuclear fission does not form any smoke. (iv) Once fully loaded a nuclear reactor can produce high amounts of energy for very long time at a stretch without having to be reloaded.
Alveoli Nephron (i) Alveoli is the functional unit of the lungs. (ii) Nephron is the functional unit of the Kidneys. (ii) A lung has about 300 million alveoli. (ii) A kidney has about a million nephrons. (iii) Alveoli provides a very large surface for the exchange of gaseous materials to take place. (iii) The Surface are of Nephrons is not very large.                                 ...
Given : potential  difference = 50 V.                  Charge = 9600 C                 time = 1 hr=3600 s So,                    
Corrosion is a process in which metals deteriorate due to chemical reaction with moisture ,air and chemicals.Rusting of iron is a major example of corrosion.Iron corrodes in presence of moisure and air.
We know that nitrogen is a inert gas and does not react with oil and fat containing food.Whereas, other gases like oxygen react with oil and fat containing food and make them rancid.Hence, to remove oxygen and prevent food from racidity food items are flushed with nitrogen.
To prevent iron from rusting paint is applied on iron articles.After applying paint iron articles are not in contact to moisture and air and hence rusting is prevented.
A shiny brown coloured element is copper (Cu) and  on heating in air it becomes black in colour because of formation of copper oxide(CuO).
In,               ( given )               (common )       ( By AA rule)     ( corresponding sides of similar triangles )              
Amount in the beginning = Rs. 10000 Interest at the end of 1st year at rate of  is  of 10000 =  Therefore, amount at the end of 1st year will be = 10000 + 800 = 10800 Now, Interest at the end of 2nd year at rate of  is   of 10800 = Therefore,, amount at the end of 2ndyear = 10800 + 864 = 11664 Since, each subsequent term is not obtained by adding a unique number to the previous term; hence,...