Directions: Read the following table carefully and answer the questions given below.
The following table shows the time taken by all of them on each day.
| Name | Thursday | Friday | Saturday | Sunday |
| Sandeep | ---- | (x + z) | ---- | (2z + x) |
| Avishek | x2 + 5x - 2 | ---- | ---- | x2 + z |
| Rajesh | ---- | x2 | ---- | y2 - 12y - 3 |
| Bhupendro | z | ---- | ---- | 8 |
| Rishu | ---- | (y - x) | ---- | 2z |
Some values are missing on the table. The values of x, y, z are positive.
Conditions:
1. The total distance covered by Sandeep in the first three days is 1500 km. The ratio between the sum of the distance travelled on Thursday and Friday and the distance travelled on Saturday and Sunday is 5 ∶ 7.
2. On Saturday Avishek travelled 480 km, and his speed was 60 km/h. The ratio of time taken by him on Thursday and Saturday is 3 ∶ 2.
3. Rajesh's speed on Sunday was 50 km/h and that day he travelled (1/3)rd of the distance travelled by Sandeep in the first three days.
4. On Saturday and Sunday Bhupendro travelled a total twice the distance travelled by Avishek on Saturday. The ratio between the distance travelled by him on Saturday and Sunday is 5 ∶ 7 respectively. He took 2 hours less time on Thursday than Sunday.