Class 8 Online Courses

Inventions Practice Tests

Inventions Online Tests

Letter Box Multiple Choice Questions (MCQ) PDF Download

Free Letter box Multiple Choice Questions (MCQ Quiz) with Answers (Letter Box MCQ PDF Book) download to learn online courses. Practice Inventions and Inventors Multiple Choice Questions and Answers (MCQs), Letter Box quiz answers PDF for online learning. The Letter Box MCQ App Download: Free learning app for water heaters, steam engine, striking clock, modern neuroscience test prep for online school classes.

The MCQ: First letter-box was discovered by; "Letter Box" App Download (Free) with answers sir jack kilby, sir albert potts, sir hans von ohain and alexander fleming for online learning. Solve inventions and inventors quiz questions, download Google eBook (Free Sample) for online learning.

Letter Box MCQs: Questions and Answers PDF Download

MCQ 1: The first letter-box was discovered by

  1. Sir Jack Kilby
  2. Sir Albert Potts
  3. Sir Hans von Ohain
  4. Alexander Fleming

MCQ 2: Letter-drop letter box was discovered by

  1. Sir William kennedy Dickson
  2. Sir John Barber
  3. Sir Philip Downing
  4. Sir Louis Pasteur

MCQ 3: In which one of the following year the first letter-box was patented by the U.S postal service?

  1. 1803
  2. 1833
  3. 1858
  4. 1847

Inventions Practice Tests

Letter Box Learning App & Free Study Apps

Download Letter Box MCQs App to learn Letter Box MCQs, Inventions Learning App, and Environmental Management MCQ Apps. Free "Letter Box" App to download Android & iOS Apps includes complete analytics with interactive assessments. Download App Store & Play Store learning Apps & enjoy 100% functionality with subscriptions!

Letter Box App (Android & iOS)

Letter Box App (Android & iOS)

Inventions App (Android & iOS)

Inventions App (iOS & Android)

Environmental Management App (Android & iOS)

Environmental Management App (Android & iOS)

DataBase Management System (MCS) App (Android & iOS)

DataBase Management System (MCS) App (iOS & Android)