Answer: C) C++ Explanation: C++ is not an Operating System.   An Operating System is a collection of system programs that manages all the other programs application programs in a computer as well as the allocation and use of hardware resources such as the CPU, Memory and the Hard Disk Drive. It acts as an interface between the hardware and the user level program. It controls and facilitates the overall operation of a computer.    Here UNIX : UNIX is a popular multi-user, multitasking operating system (OS) developed at Bell Labs.   Windows NT : Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993.   DOS : DOS is Disk Operating System. The term DOS can refer to any operating system.   C++ : C++ is a programming language and computing platform.   Hence, C++ is not an Operating System.

Answer: D) 6011 hrs Explanation: From March 6th to November 11th, there are 250 days and Thus 250 x 24 hoursSo from Mar 6th 9AM to Nov 11th 8PM, there will be 250 x 24 + 11 hours = 6011 hrs.

Answer: B) 300, 200, 250 Explanation: A's 5 days work = 50%   B's 5 days work = 33.33%  C's 2 days work = 16.66%     [100- (50+33.33)]  Ratio of contribution of work of A, B and C = 50 : 3313 : 1623 = 3 : 2 : 1    A's total share = Rs. 1500  B's total share = Rs. 1000  C's total share = Rs. 500     A's one day's earning = Rs.300   B's one day's earning = Rs.200   C's one day's earning = Rs.250

Answer: D) 203 Explanation: The given number series is 125,   138,   164,   ?,   255   125   125 + 13x1 = 138   138 + 13x2 = 164   164 + 13x3 = 203   203 + 13x4 = 255       Hence, the missing number in the series is 203.

Answer: B) 170 lit Explanation: Given A alone can fill the tank of capacity 240 lit in 16 hrs. => A can fill in 1 hr = 240/16 = 15 lit => B alone can fill the tank of capacity 240 lit in 12 hrs. => B can fill in 1 hr = 240/12 = 20 lit Now, (A + B) in 1 hr = 15 + 20 = 35 lit But they are opened for 2 hrs => 2 x 35 = 70 lit rae filled Remaining water to be filled in tank of 240 lit = 240 - 70 = 170 lit.

Answer: C) 1/6 Explanation: Given X can do in 10 days  => 1 day work of X = 1/10   Y can do in 15 days  => 1 day work of Y = 1/15   1day work of (X + Y) = 1/10 + 1/15 = 1/6   Given they are hired for 5 days  => 5 days work of (X + Y) = 5 x 1/6 = 5/6  Therefore, Unfinished work = 1 - 5/6 = 1/6

Answer: B) 210 Explanation: Let the required number be 'p' We know, sum of angles in a triangle are 180 deg According to given data, p - p/7 = 180 7p - p = 180 x 7 => 6p = 1260 => p = 1260/6 = 210

Answer: B) Electron transport chain Explanation: