Consider the following relational schema: 
Which of the following options is/are correct SQL query/queries to retrieve the names of the students enrolled in course number (i.e., courseno) 1470?
| List-I | List-II |
|---|---|
| (A) SUBSTR() | (II) To extract a substring from a string. |
| (B) TRIM() | (IV) To remove spaces from both sides of the string. |
| (C) INSTR() | (I) To find the position of a substring in a string. |
| (D) LEFT() | (III) To extract characters from the left side of the string. |
Given the following table:
| ENO | SALARY |
|---|---|
| A101 | 4000 |
| B109 | NULL |
| C508 | 6000 |
| A305 | 2000 |
State the output of the following query:
SELECT COUNT(SALARY) FROM EMPLOYEE;

A ladder of fixed length \( h \) is to be placed along the wall such that it is free to move along the height of the wall.
Based upon the above information, answer the following questions:
(iii) (b) If the foot of the ladder, whose length is 5 m, is being pulled towards the wall such that the rate of decrease of distance \( y \) is \( 2 \, \text{m/s} \), then at what rate is the height on the wall \( x \) increasing when the foot of the ladder is 3 m away from the wall?