Simplification the following equations shown below

The length of the chord of a circle is 8 cm and perpendicular distance between center and the chord is 3 cm. Then the radius of the circle is equal to:

At what approximate time between 4 and 5 am will the hands of a clock be at right angle ?

Direction: In the following questions two equations numbered I and II are given. You have to solve both the equations and Give answer

Give answer (A) If x > y
Give answer (B) if x ≥ y
Give answer (C) if x<y
Give answer (D) If x ≤ y
Give answer (E) if x=y or the relationship cannot be established.

I. x³-371=629
II.y³ – 543 =788

A, B and C invested amounts in the ratio 3 : 4 : 5 respectively. If the schemes offered compound at the rate of 20 % per annum, 15 % per annum and 10 % per annum respectively, then what will be the ratio of their amounts after 1 year? 

If Jhanavi borrowed Rs.1,25,000 at 8% compounded, what will be the amount to be paid back at the end of 2 years?