Whats the distance between the points a(-1,5), b(0,4)

Leo is going to use a random number generator 4 0 0 400 times. each time he uses it, he will get a 1 , 2 , 3 , 4 , 1,2,3,4, or 5 5. what is the best prediction for the number of times that leo will get an odd number?

Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?

1) prove that 731^3−631^3 is divisible by 100 2) prove that 99^3−74^3 is divisible by 25