1. Letter

4. Post Box

5. Post Office

2. Postman

3. Delivery

So, the order is – (1, 4, 5, 2, 3)

Hence, option D is correct answer.

Milk is a bi-product of cow, Egg is also bi-product of Hen.

Hence, option B is the correct answer.

● The Constitution of India is the longest written constitution of any country in the world.

● The Constitution of Monaco is the shortest written constitution, containing 10 chapters with 97 articles.

● The Constitution of the United States is the world's oldest continuously-active codified constitution, having been in force since 1789.

• Napoleon Bonaparte was defeated in the Battle of Waterloo.

• The Battle of Waterloo was fought on 18 June 1815, near Waterloo in Belgium.

• Napoleon Bonaparte was a French military and political leader.

• As Napoleon I, he served as the Emperor of the French from 1804 until 1814.

Let the total work be 1 unit.

Given: Ravika alone can complete three- fifth of a work in 105 days

⇒ 3/5-unit work ≡ 105 days

⇒ 1-unit work ≡ 105 × (3/5) = 175 days

∴ Ravika completes the whole work in 175 days.

Given: Mallika can complete one third of work in 50 days

⇒ 1/3-unit work ≡ 50 days

⇒ 1-unit work ≡ 50 × 3 = 150 days

∴ Mallika completes the whole work in 150 days.

Ravika and Mallika working together complete the work in  days

∴ Ravika and Mallika working together complete the 26/35 of the work

=  = 60 days

The given sentence is in the active voice and it uses a modal verb.

The structures for active/passive voices for modal verbs are:

Active: Subject + modal verb + verb (Ist form) + object...

Passive: Object + modal verb + be + verb (IIIrd form) + by + subject...

So, with the help of the above structures, we can convert the given sentence into passive voice: A pandemic can be spread worldwide within days by air travel.

Hence, option A is the correct answer. 

The given sentence is in Direct Speech because it quotes actual words. Therefore, it must be changed into Indirect Speech.

We notice that the reporting verb is in the Past tense (‘said’). Hence, a change will be made in the tense of the reported speech.

Also, the first person of the reported speech is changed according to the subject of reporting speech.

The present perfect tense (has been scheduled) is changed to past perfect tense (had been scheduled). 'Tomorrow' is changed to 'the next day'.

Therefore, the sentence in Indirect Speech will be option D i.e. The manager said that the meeting had been scheduled for the next day.