Choose the antonym of the word

What will come in place of '?' in the following equation, if '+' and '÷' are interchanged and '×' and '–' are interchanged?  

If 18 August 2000 was Friday, then what was the day of the week on 21 August 2005?

Select the number from the given options to complete the series.

35, 38, 43, 50, 59, ___

‘A + B’ means ‘A is the brother of B’.

‘A – B’ means ‘A is the wife of B’.

In a certain code language, 'MINT' is coded as '9735' and 'NEAR' is coded as '4568'.

What is the code for 'N' in the given code language? 

Statements:

Some mugs are jars.

All jars are bottles.

All glasses are mugs.

Conclusions:

If G means '–', C means '×', D means '+', B means '÷', then what will come in place of the question mark (?) in the following equation?

Three of the following letter-clusters are alike in some manner and one is different.

Select the one that is different.