MCQ PracticeAn iron pipe 20 cm long has exterior diameter equal to 25 cm. If the thickness of the pipe is 1 cm, then the whole surface of the pipe is :Subject: MathematicsTopic: Volume And Surface AreaA3068 cm 2B3168 cm 2C3268 cm 2D3368 cm 2Correct Answer: BPractice QuizBack to MCQsRelated MCQsCurrent flows in a circuit whenEighttenths coulomb passes a point in 4 s. The current in amperes isThe unit of electrical charge is the