Prove that the feet of perpendiculars from the origin on the lines x+y=4 , x+5y =26 and 15x -27y= 424 are collinear.
Calculate the number of calories required to raise the temperature of 50 g of water from 20 Celcius to 40 Celcius
A circular arc of length 2π cm subtends an angle [1/π] rad at its centre. Radius of circular arc is?