(6) If the angles of a triangle are in the ratio 3:4:5, find the smallest angle in degrees and the greatest angle in radians. (7) Prove the following identity: tan 50+tan 30 4 cos20 cos40 - tan 50 tan 30 (8) The lines 2x-3y =5 and 3x-4y =7 are the diameters of a circle of area 154 square units .Find the equation of the circle. (9) Find the equation of the circle with origin as centre passing the vertices of an equilateral triangle whose median is of length 3a. (10) Find the equation of a circle whose centre is at (4,-2) and 3x-4y+5=0 is tangent to circle.