Which of the following symbols should replace the blanks in the given expression to make the expressions X ≤ Z true?

O = X = M _ Q _ Z

Study the following information carefully and answer the questions given below-
Two families with 14 members, includes 7 males and 7 females .C is the grandfather of M and P and he is an engineer .C has one sister O who is lawyer. K is an engineer and I is a lawyer, both of them are son-in-law of E. F,G and H are daughters of E and C and out of them only H is unmarried and is a teacher. Other sisters of H are housewives. G is not married with an engineer. M and P are sons of K. One of the grandson of C is an engineer. O has one married son D and one unmarried daughter J. L is the aunt of Z and she is working in a bank. F is sister-in-law of L and she is a housewife. Z is a student and his father is an engineer. In the family only P is a doctor. J is lawyer. L is the sister of K.

How two male engineers from same generation are related to each other? 

Vikram started from point R and walked straight 7 km west, then turned left and walked 2 km and again turned left and walked straight 4 km. In which direction is he from R?

Direction : Study the following information carefully and answer the questions given below.
In a certain code language:
“Never talk between others” is coded as “sm nt ro fi”
“Others should be helpful” is coded as “ro el ac jq”
“Never be time specific” is coded as “fi dg el pa”
“Focus between specific hours” is coded as “hy dg nt ks”

The code “el” is coded as which of the following word?

Select the number from among the given options that can replace the question mark (?) in the following series. 

5, 18, 70, 278, ?

Simran walks 10 kilometers towards north. From there, she walks 6 kilometers towards south. Then, she walks 3 kilometers towards east. How far and in which direction is she with reference to her starting point?

Study the following information carefully and answer the questions given below:

P, Q, R, S, T, V and W are seven students of a school. Each of the studies in different standards from Standard IV to Standard X not necessarily in the same order. Each of them has favorite subject is English, Science, History, Geography, Mathematics, Hindi and Sanskrit not necessarily in the same order. Q studies in VII Standard and does not like either Mathematics or Geography. R likes English and does not study either in V or IX. T studies in VIII Standard and likes Hindi. The one who likes Science studies in X Standard. S studies in IV Standard. W likes Sanskrit. P does not study in X Standard. The one who likes Geography-studies in V Standard.

In which standard does W study? 

A boy was cycling northward, then he turned left and rode 3 km. He again turned left and rode 13 km after which he found himself 5 km South-West of the starting point. How far did he ride northward, initially?